Shoeless GTM #501 Here we go!!! [Archive] - Page 3

Shoeless

09-08-2020, 12:49 PM

I hope you guys enjoyed your Labor Day weekend!! I put in a solid two and a half days in the garage working GTM wiring. I'm making progress on the Mil-Spec planning of the chassis side of things, but I need to get everything else somewhat in their place so I know where to make branch points and how long each leg will run. I'll fully document that harness on my other post.

I spent the majority of the weekend in the drivers seat under dash area. First order of business was installing a LED dimmer switch for the steering wheel and console buttons. For console buttons I got the same billet ones James did from Australia. Once I testing them to see how bright they were, I opted for a dimming switch. I mounted this just below the power distribution block next to my steering column and next to the Infinitybox master cell. You can see it clekoed in place in the second pic. I now have permanently mounted and power steering wheel button lights.

https://i.imgur.com/w5TeQ6F.jpg

https://i.imgur.com/nA1LWmW.jpg

https://i.imgur.com/HDHZWaZ.jpg

Here is a close up of the clock spring circuits. All labeled and connected with glue lined heat shrink butt connectors. I'll cover this with DEI Easy Loom once I'm happy with the full run. As I was inspecting the donor column plug, I wasn't too happy as I noticed a little damage. So I'm going to order some Deutsch DTM connectors to replace the steering column plug and windshield wiper controls to allow me to still be able to remove the column if I need to.

Then finished off yesterday starting to run all the Infinitybox Master Cell inputs. I threw a few p-clips in there to hold things for the moment. I kind of like how nice and easy I'll be able to make separate branches come out of this general area, so I'll probably stick with this general concept to hold the wiring under the dash out of the way. Things are coming together.

https://i.imgur.com/UkKsVYF.jpg

https://i.imgur.com/Qpb098l.jpg

Shoeless

09-12-2020, 06:04 PM

Worked on organizing some of the Master Cell inputs this morning and then shifted over to labeling and figuring out the wiring on my new Billet Automotive buttons. These are from the same company that James picked his up from in Australia. I was fully expecting 2 weeks for delivery, but I think 5 days after my order they showed up. Top notch quality and I love the look. I have two different versions, momentary and latching. The momentary will be for the Windows Up/Down and Start. The latching will be for Data Log, Fog/Interior/Hazard Lights. The momentary will be green LED all the time and the latching will be green when open and red when latched closed.

I'll probably need to add some diodes to the wiring to block voltage going into the Infinitybox Master Cell when the switches are in the open state (interesting how the switches are wired up to change colors when open or latched) and also need to find out if I can switch to chassis ground for the Data Log. Right now the ECU instructions state to use Sensor Ground from the ECU to activate Data Logging, but if I need to do that I won't be able to have the color changing option. I've got a message sent off to AEM to see what they think about using chassis ground.

https://i.imgur.com/mufaK1Q.jpg

https://i.imgur.com/MCgeLRy.jpg

https://i.imgur.com/F0zsPUq.jpg

https://i.imgur.com/5dnCB21.jpg

https://i.imgur.com/VWiki2j.jpg

Shoeless

09-21-2020, 07:33 PM

More and more wiring on Shoeless GTM, I figure I will be saying this for a bit, but one circuit at a time and she'll be done soon. I ditched the factory plugs for the steering column and opted for a Deutsch DTM 12 way connector. Cleaned this up nicely.

https://i.imgur.com/XaZVBuK.jpg

https://i.imgur.com/GIOzJav.jpg

https://i.imgur.com/fXZXkw8.jpg

https://i.imgur.com/H9rMtcJ.jpg

https://i.imgur.com/pMIZrpr.jpg

beeman

09-22-2020, 10:02 AM

Quite an improvement! Great work as usual.

Shoeless

09-24-2020, 04:47 PM

Quite an improvement! Great work as usual.

Thank you Sir!! Definitely takes a bit more time, but I think it’s totally worth it to clean it up and do it in a manner that will be very user friendly.

KGTM

09-25-2020, 12:53 PM

This looks good but really not sure why you would change the OEM connector, I bought he connecting end and pins and the keep the OEM side excapply the same, good thing about that is when it goes bad I just replace it no need for new wiring again.

beeman

09-25-2020, 08:53 PM

I'd say his ain't gonna go bad

Shoeless

09-26-2020, 07:40 AM

Several reasons really. The donor plug I got already had minor damage to it allowing one of the pins I needed for a ground to not fully lock in place, it was relying on the locking bridge on the back to hold it in place. Deutsch DTM is far superior compared to OEM, It's a hell of a lot more compact and also a semi-sealed connection. Not to mention I'll use several DTM plugs throughout the car, so they all will use the exact same pin and sockets, unlike every other plug I've come across needing their own special pins. Plus I get all this for about $18, its a no brainer for me.

KGTM

09-26-2020, 12:45 PM

I actually have two signal switches and one went bad or was bad and has to replace it, so it was really nice that was just OEM plug in.

The concept goes for other connector that are in columns that is used, like the wiper, telescopic motor/switch and position sensor connectors.

Was Just my two cents for you as owner and next guys who will make a change due to all sort of resean, may be even accidental damage.

Mostafa

Shoeless

09-26-2020, 02:20 PM

Deutsch DT and DTM plugs are about the most serviceable plugs on the market. You will notice on OEM pins they have a lock retaining feature as part of the metal pin/socket portion of the pin/socket itself and typically once removed with a depinning tool, you have to bend that metal tab back or it won't lock in the plug itself. Deutsch DT/DTM has the locking feature as part of the plug with a locking wedge. Super easy to use.

I will be using some OEM plugs along the way BTW. Like for the wiper motor plug. I was able to source replacement pins for this 5 pin plug (two different size pins in the one plug alone) and will rebuild it using the OEM plug.

KGTM

09-27-2020, 12:29 PM

Delphi connectors are also very good.

I am sure these will work for you, you have so much wiring and connections it is scary.

Mostafa

cgundermann

09-27-2020, 01:02 PM

jamesfr58

09-28-2020, 07:59 PM

Like those switches, they work great and they make all kinds of them with different graphics.

Shoeless

10-03-2020, 01:52 PM

Taking a break from the wiring for a minute as my carbon fiber tubing FINALLY came in. They were on backorder since the beginning of Covid, so this was a long time coming. I finally have the intake all mocked up. Just need to add a port for inlet temp and a breather for the engine, and make a small bracket to hold it in place and I'm good to go on this.

https://i.imgur.com/cUf56AH.jpg

https://i.imgur.com/sUFC9k4.jpg

https://i.imgur.com/oBZyyf4.jpg

https://i.imgur.com/MA9aOIP.jpg

https://i.imgur.com/edn7Fit.jpg

https://i.imgur.com/WPqHC4i.jpg

dlud

10-03-2020, 07:15 PM

Shoeless

10-03-2020, 07:47 PM

Nice. Love the carbon tubes.
Are you going to attach an overflow tank to the coolant reservoir? I asked as I spent a good portion of today trying to find a suitable spot for one vs simply running an overflow tube to the ground.

This really turned out better than anticipated, so I'm very pleased with the look.

I've kicked around the idea of a coolant overflow tank, but I'm really running out of real estate. On the other hand, if I don't I need to make a decision on where an overflow would run out. What are you thinking tank wise or where are you thinking for your overflow discharge point?

dlud

10-03-2020, 11:10 PM

I picked up a 3" x 10" stainless overflow tank. I'll take a photo showing where I've temporarily mounted it. I think it's an ok solution but I'm working a bit in the dark as my body is out being painted and I'm operating on memory as to how much room I have to work with.

Ajzride

10-04-2020, 10:25 AM

Having an overflow tank makes bleeding a mid-engine car so much easier. Even a really small one would be better than nothing.

dlud

10-04-2020, 07:38 PM

Here is where I've temporarily located mine. Not the easiest to access once the body is on and I'm hoping I have enough room.
135928

Shoeless

10-04-2020, 08:53 PM

Let me preface this by saying I’m relatively new to learning the ins and outs of an additional overflow tank, but I remember discussing this with Shane and Crash. It may have been on my thread or another one, I’d have to look back. They shared that the additional overflow tank should be clear and somewhere visible so you can actually see if it need draining. I think Crash even is using just a generic Dorman clear overflow tank. I also vaguely remember the conversation about it being higher so it can actually drain back. I could be wrong on this one, maybe they will chime in and refresh my memory.

I originally thought about a Motion Raceworks Black billet can as it would match my transaxle breather, but decided to hold off.

dlud

10-05-2020, 12:05 AM

The expansion tank certainly needs to be the high point of the system. The recovery/reservoir does not. The tank I'm using has an inlet/outlet on the bottom that is attached by clear hose to the expansion (Canton) tank. I also has an overflow which drains the excess from the reservoir before it overflows. You can see the overflow line in my photo that goes to ground. https://www.amazon.com/BLACKHORSE-RACING-Radiator-Overflow-Polished-Stainless/dp/B0742CKVRJ/ref=sr_1_2?dchild=1&keywords=3x10%2Bcoolant%2Boverflow%2Btank&qid=1601874087&sr=8-2&th=1
The location of the tank isn't ideal but give the space limits it seemed like the best choice.

dlud

10-05-2020, 12:07 AM

On the difference between expansion tank, recovery/reservoir and catch can see: https://blog.cantonracingproducts.com/blog/setting_up_your_cooling_system_expansion_vs_recove ry

Shoeless

10-05-2020, 09:18 AM

Great discussion here and thanks for the article, always good for me to read up and make sure I'm knowledgeable.

I will say when I looked at this some time ago I was really keen on the below tank for Canton. It would be small enough that I could have Shane make me a bracket and mount it literally right next to my expansion tank. Something I should revisit since I'm starting to fill up that area with other braided hoses and taking up real estate.

https://www.cantonracingproducts.com/canton-80-201c-aluminum-recovery-tank-universal-1-75-qt-chamfered-style/

crash

10-05-2020, 10:39 AM

A recovery tank should have a inlet/outlet that is at the bottom of the tank so that coolant is able to flow back and forth depending on volume changes due to heat in the engine. It should be connected to the radiator cap overflow port. Clear or "clearish" so that fluid level can be seen is helpful. It does not have to be the highest point. That requirement is reserved for the expansion/header tank.

Shoeless

10-17-2020, 11:30 AM

I've been kicking around ideas for dressing up the engine compartment a bit and fellow GTM owner/builder Brian Bohannon recommended I check out Anderson Composites. They had exactly what I was looking for, a one piece real carbon fiber plenum cover. There were tons of companies offering a 2 piece hydro-dipped option out there, but that would not fit my theme. As with the OEM plenum cover on an LS3 it required a little trim on the forward edge to clear the firewall. Masked it up and broke out the diamond cutting wheel and went to town. A little trim and touchup with a hand file and it came out EXCELLENT. There was one other small area on the side I needed to trim to clear the plenum, but that was a piece of cake. I dropped in a before pic just to show the improvement in look :cool:

https://i.imgur.com/GLHcGWI.jpg

https://i.imgur.com/9ZE4gek.jpg

https://i.imgur.com/nxwB35E.jpg

https://i.imgur.com/yLG7i0X.jpg

https://i.imgur.com/vzFXrWo.jpg

https://i.imgur.com/yc1sbMD.jpg

Keith1

10-18-2020, 10:04 AM

You're engine bay is gorgeous! Nice work.

Shoeless

10-18-2020, 06:05 PM

You're engine bay is gorgeous! Nice work.

Thank you Sir!!! There are so many skilled builders here, it's great sharing the vision in my head when it all comes to reality with everyone. Especially when it turns out as nice as these CF mods have.

Roger Reid

10-26-2020, 10:54 PM

The engine bay looks great. Where do you have the mass air flow sensor (MAF) located.

Shoeless

10-27-2020, 06:06 AM

The engine bay looks great. Where do you have the mass air flow sensor (MAF) located.

Hey Roger,

Thank you Sir. I’ll be using speed density for my tuning so no need for a MAF on my setup.

I do need to find a spot for air inlet temp sensor. I’m thinking in the last elbow before the throttle body on the bottom side just above the transaxle so it’s hidden and reading the last bit of air before it enters the throttle body.

What do you guys think of that spot for the AIT sensor?

VRaptor SpeedWorks, LLC

10-27-2020, 08:14 AM

Shoeless

10-27-2020, 08:21 AM

Except at idle, from the time the air enters the CAI til it enters the engine, I doubt there's enough time for the temp to change significantly....so I doubt it matters all that much where you put the sensor?

Great point here.

Funny enough I posed this question on a tuning Facebook page I'm on and got a wide range of proposed locations, so much so that it would be inline with your response Shane. Likely doesn't really matter. Thanks for the quick feedback.

beeman

10-27-2020, 08:36 AM

Are you going to be able to place a barrier between the header heat and the cone filter? As designed, there probably is not a lot of air inflow into the GTM rear side intakes, but this is probably improved with increased venting of the engine bay.

Shoeless

10-27-2020, 10:02 AM

crash

10-27-2020, 10:03 AM

Shoeless

10-27-2020, 10:10 AM

beeman

10-27-2020, 11:53 AM

Hey Beeman,

I'm definitely planning on adding some side scoops in the 1/4 windows to help with airflow into this region of the engine bay. I'm wondering which would provide better flow in:

1. Shane's 1/4 window Scoops
2. Shane's 1/4 window NACA Ducts

NACA scoops need attached flow to work. For function in that location, you will need a scoop.

Apexspeedtech

10-27-2020, 12:17 PM

My theory is that while it MIGHT not make a difference, mounting the AIT as close to the butterfly as possible reduces any uncertainty, so as long as it is practical, why not mount it as close as possible? We run a rubber connector at the throttle body and I put the sensor in that boot.

Don't underestimate the issues it can cause at idle; poorly setup AIT correction can cause lean mixtures resulting in stalling, idle instability and worse, detonation if you accelerate aggressively after a long heat-soak period. My preference is to use an ECU that has a "charge temperature approximation table." Typically, these define air charge temp as a % contribution of engine temp versus AIT, as a function of load & RPM. At low airflow through engine temp has more of a heating effect on the incoming air, so you reduce reliance on the air intake temp sensor and mitigate the effects of heat-soak. If that's not an option, at least on naturally aspirated motors a work around is to limit your AIT correction to the maximum ambient temps you'll reasonably see.

Shoeless

10-27-2020, 06:40 PM

Don't underestimate the issues it can cause at idle; poorly setup AIT correction can cause lean mixtures resulting in stalling, idle instability and worse, detonation if you accelerate aggressively after a long heat-soak period. My preference is to use an ECU that has a "charge temperature approximation table." Typically, these define air charge temp as a % contribution of engine temp versus AIT, as a function of load & RPM. At low airflow through engine temp has more of a heating effect on the incoming air, so you reduce reliance on the air intake temp sensor and mitigate the effects of heat-soak. If that's not an option, at least on naturally aspirated motors a work around is to limit your AIT correction to the maximum ambient temps you'll reasonably see.

Thanks for the feedback on this one Neel. Obviously being a complete newbie to the tuning world, its nice to see this feedback with regard to a specific situation and then going back to my user guide and notes and seeing the AEM Infinity does support a Charge Temp Blend option. Essentially I can set up this table to use a blend of air temp and coolant temp based on RPM, with a number ranging from 0 (more Air Temp) to 1 (more Coolant Temp). At lower RPMs I will chose lets say 0.8 for RPMs 500-1500 (taking more of the blend from coolant temp) and can then start to lower this number by 0.1 as RPM increase every 500 rpm (to shift more of the blend to Air Temp).

dlud

10-27-2020, 08:32 PM

Hey Beeman,

I'm definitely planning on adding some side scoops in the 1/4 windows to help with airflow into this region of the engine bay. I'm wondering which would provide better flow in:

1. Shane's 1/4 window Scoops
2. Shane's 1/4 window NACA Ducts

James in Wyoming did an analysis of these (in cfd?)...the side scoops were more effective. It's on his build thread (in answer to my same question).

Shoeless

10-28-2020, 07:13 AM

James in Wyoming did an analysis of these (in cfd?)...the side scoops were more effective. It's on his build thread (in answer to my same question).

I think I remember that now that you mention it, thanks for refreshing my memory dlud.

Apexspeedtech

10-29-2020, 02:25 AM

its nice to see this feedback with regard to a specific situation and then going back to my user guide and notes and seeing the AEM Infinity does support a Charge Temp Blend option. Essentially I can set up this table to use a blend of air temp and coolant temp based on RPM, with a number ranging from 0 (more Air Temp) to 1 (more Coolant Temp). At lower RPMs I will chose lets say 0.8 for RPMs 500-1500 (taking more of the blend from coolant temp) and can then start to lower this number by 0.1 as RPM increase every 500 rpm (to shift more of the blend to Air Temp).

AEM's ChargeTempBlend function leaves something to be desired; every other ECU I've seen with a charge temp approximation function has a load axis, I don't understand why AEM does not. This omission leaves you open to heat soak issues during low-speed steady state cruise. The torque curve of an LS motor combined with high engine compartment temps, typical of a mid engined car at low speeds make AIT heat soak issues even more costly here. Leaned-out mixtures and transient detonation is one thing at idle, its another thing when you're actually motoring along in top gear. For race cars, this can be an issue during yellow flag laps when you're trying to save fuel. In your case, be extra careful not to lug your motor on hot days.

Shoeless

10-29-2020, 10:16 AM

AEM's ChargeTempBlend function leaves something to be desired; every other ECU I've seen with a charge temp approximation function has a load axis, I don't understand why AEM does not. This omission leaves you open to heat soak issues during low-speed steady state cruise. The torque curve of an LS motor combined with high engine compartment temps, typical of a mid engined car at low speeds make AIT heat soak issues even more costly here. Leaned-out mixtures and transient detonation is one thing at idle, its another thing when you're actually motoring along in top gear. For race cars, this can be an issue during yellow flag laps when you're trying to save fuel. In your case, be extra careful not to lug your motor on hot days.

Awesome, thanks for the feed back on this one. I'm also hoping all the heat management items I'll incorporate will help me with this as well.

Apexspeedtech

10-29-2020, 01:21 PM

Awesome, thanks for the feed back on this one. I'm also hoping all the heat management items I'll incorporate will help me with this as well.

Yeah, it’s usually not a problem but I feel like your GTM is the perfect storm for this: lots of low end grunt, light chassis, 6 speed gearbox and mid-engined in a place with hot summers!

cgundermann

11-12-2020, 10:35 PM

You're engine bay is gorgeous! Nice work.

I’ll second that, very-very nicely done.

Chris

Shoeless

11-13-2020, 12:27 PM

I’ll second that, very-very nicely done.

Chris

Thank you for the kind words Chris. I've got some test samples of installing fittings into the CF intake for Engine Breather and IAT Gauge that I'll be doing this weekend. Then a support piece for the intake and that part is fully functional and complete.

Shoeless

11-13-2020, 09:30 PM

Little more work in the garage this afternoon once the day job slowed down.

I wanted to do a little refinement on the CF intake and do a test run with some of the 3M panel bond for the bung I'm looking to bond in place. I ended up trimming 1/4" off the last 90 deg bend that was near the expansion tank and that gave it the desired spacing I was looking for. From there I drilled some holes and used a rotary file to open the holes up on some of the drop pieces from the original construction and I'll use an old fitting and old terminal for the test. I scuffed everything up, cleaned with alcohol, and mixed up some panel bond.

https://i.imgur.com/bBsp5gw.jpeg

https://i.imgur.com/cskqkLi.jpeg

From there I installed my oil cooler thermostat bypass after getting in all the fittings to fit in the darn small space to run AN lines to the back of the car. I essentially needed to get my oil pressure and temperature gauge in place so that I can start to lay out the main harness for the engine, so this was the best option. I was going to run the Bosch sensor off the thermostat block, but someone pointed out I needed to get the probe of the sensor in the "flow" to measure accurately, so I had to change my plans. Just install the bypass valve, put the sensor in what its final location will be, and then loop some line back to the return port on the cooler. Essentially no cooler will be needed/used for the break in and go carting/tuning. Once I get the body ready to get in place and diffuser all set up I'll plumb this and the transaxle to the their respective coolers. When I go to fill the engine with break in oil I'll pay particular attention to needing just a tad bit more oil that what's called for.

I'll also likely build another heat shield for this side of the engine to protect against the exhaust. Simple enough to add a piece of sheet metal to the current setup.

https://i.imgur.com/RHFP0sj.jpeg

https://i.imgur.com/l2frq1o.jpeg

https://i.imgur.com/bvi5zoV.jpeg

Shoeless

11-14-2020, 03:54 PM

Today was a pretty big day for me on the GTM. I realized I had gotten to the point on the wiring this morning that the next step would be to connect and power up the Infinitybox system for the first time.

I pulled out my documentation from Infinitybox that I had been marking off as I was doing things, double checked from beginning to end, and then hook her up. Success!, she is alive. I as able to upload the custom configuration that Jay put together for me and that went perfectly with zero problems. Time to start checking the circuits I have hooked up and work through a couple items I have questions of for Jay. Overall, amazing day!!!!

https://i.imgur.com/KsCTsbW.jpeg

https://i.imgur.com/vqFtNqx.jpeg

https://i.imgur.com/BTvlMhN.jpeg

https://i.imgur.com/RyCSThK.jpeg

https://i.imgur.com/wyTL8WL.jpeg

cgundermann

11-14-2020, 05:05 PM

Thank you for the kind words Chris. I've got some test samples of installing fittings into the CF intake for Engine Breather and IAT Gauge that I'll be doing this weekend. Then a support piece for the intake and that part is fully functional and complete.

I did a lot of real carbon fiber laminations on my Cobra (dash, trunk etc.) and love it. I’ve been closely following your build. I’m considering building a GTM or an SLC. I truly appreciate your thoughtfulness and attention to detail...

Chris

Shoeless

11-14-2020, 09:39 PM

I did a lot of real carbon fiber laminations on my Cobra (dash, trunk etc.) and love it. I’ve been closely following your build. I’m considering building a GTM or an SLC. I truly appreciate your thoughtfulness and attention to detail...

Chris

I've got a picture in my head of what this whole project will look like and I hope to keep the CF accents tasteful throughout. The guy that did the CNC router work and acrylic pour on my CF steering wheel button plate actually holds classes on CF skinning and different acrylic classes and might be something I can actually get my wife interested in participating in with me so I can learn more on the processes. I've also picked up a nice vacuum pump and supplies for vacuum bagging from a guy who built a fiberglass top for his boat.

I'm really liking the GTM build and do plan on one more build later in life down the road. Who knows what it will be by the time I get to retirement age, but if that were right now the F9 looks very interesting, but an SLC would be high on the list.

cgundermann

11-14-2020, 10:01 PM

Shoeless

11-15-2020, 07:20 PM

You can definitely overdue it with CF, so I like your tasteful approach. The carbon fiber class sounds really interesting, but right now I’ve gotten into 3D printing and modeling and have been really trying to master my TIG welding skills. I want to incorporate these two attributes into my next build. I’m retired now and really want to stretch my build skills with my next project. Thanks for the detailed build thread, it keeps me motivated. I’m moving next month and will have an even bigger shop, and when the dust settles will finalize my next project.

Chris

Those are two areas I DEFINITELY want to get into one of these days. I've been leading a very interesting project at Pratt & Whitney where I work in West Palm Beach on working towards product insertion of 3d printing a large group of parts on one of our Turbo Jet applications. None of this one for one part substitution either, we're consolidating over 90% of the parts in the static hot section into one 3d printed piece. Pretty cool project and I have been fortunate enough to be able to file for 7 patent applications over the last two years, all on metal 3d printing.

Shoeless

11-15-2020, 07:24 PM

I got some mixed results on my 3M panel bond project, and I think I know why. The brass fitting on the left is rock solid, no issues, and I almost torqued it to the point the CF would break, but backed off a bit. The one on the right had me scratching my head for a second until I remembered that this two part bonding material is two colors and is not a 1:1 mix, there is more of the black material than the other. I don't think I mixed it well enough before I applied it. When I put a wrench on it and torqued it, the bonding material gave away and almost crumbled. Like it didn't have the hardener in it. Maybe try one more sample before I do the real deal part.

https://i.imgur.com/TMZsYeI.jpg

cgundermann

11-15-2020, 08:09 PM

Those are two areas I DEFINITELY want to get into one of these days. I've been leading a very interesting project at Pratt & Whitney where I work in West Palm Beach on working towards product insertion of 3d printing a large group of parts on one of our Turbo Jet applications. None of this one for one part substitution either, we're consolidating over 90% of the parts in the static hot section into one 3d printed piece. Pretty cool project and I have been fortunate enough to be able to file for 7 patent applications over the last two years, all on metal 3d printing.

That’s freaking awesome - very cool! I went to school to be an engineer and changed my degree at the last minute so that I could graduate on time and go to flight school for the Marine Corps. Afterwards, I was a collision reconstructions for 26 years and love material design and applied mathematics/physics. Being retired now, I’m doing those loves of my life...

Don’t want to steal your thread with life stories and a bromance, but my better half and my daughters all vote for the GTM - so I’ve finally decided after months of deliberation that’s going to be my next build. First part of next year it is, hopefully FFR has a sale again!

Chris

Shoeless

11-15-2020, 08:45 PM

That’s freaking awesome - very cool! I went to school to be an engineer and changed my degree at the last minute so that I could graduate on time and go to flight school for the Marine Corps. Afterwards, I was a collision reconstructions for 26 years and love material design and applied mathematics/physics. Being retired now, I’m doing those loves of my life...

Don’t want to steal your thread with life stories and a bromance, but my better half and my daughters all vote for the GTM - so I’ve finally decided after months of deliberation that’s going to be my next build. First part of next year it is, hopefully FFR has a sale again!

Chris

No worried on a little side track discussion :cool:. My posts have kind of been all over a bit here lately, but I love sharing everything I'm working on. I did my BS in Aerospace Engineering and then went back and got my MBA in Aviation with a Finance Focus. My "day job" at work is Aftermarket Program Manager in our APU Business, but I get to keep working on the Additive Manufacturing project as I see a real cost savings opportunity from my last role managing our Cost Reduction Team.

It will be nice to have another GTM building on board, there are obviously very few of us. Congrats on making the decision, and I'm sure FF will slide in some specials. I made sure to take advantage of a 50% rear wing and I know I got a few others, but can't remember them at the moment. I visited FF last year and saw 3 GTMs being packaged up, so I know there are more builders out there than are actually posting on the forums. I know it takes time and effort, but I truly enjoy the sharing, learning, and camaraderie that comes with it. My build would be nowhere near its current state if it wasn't for these forums and the builders before me.

cgundermann

11-15-2020, 08:59 PM

No worried on a little side track discussion :cool:. My posts have kind of been all over a bit here lately, but I love sharing everything I'm working on. I did my BS in Aerospace Engineering and then went back and got my MBA in Aviation with a Finance Focus. My "day job" at work is Aftermarket Program Manager in our APU Business, but I get to keep working on the Additive Manufacturing project as I see a real cost savings opportunity from my last role managing our Cost Reduction Team.

It will be nice to have another GTM building on board, there are obviously very few of us. Congrats on making the decision, and I'm sure FF will slide in some specials. I made sure to take advantage of a 50% rear wing and I know I got a few others, but can't remember them at the moment. I visited FF last year and saw 3 GTMs being packaged up, so I know there are more builders out there than are actually posting on the forums. I know it takes time and effort, but I truly enjoy the sharing, learning, and camaraderie that comes with it. My build would be nowhere near its current state if it wasn't for these forums and the builders before me.

The members on the Forum are awesome and there is some extreme talent and innovation. The GTM group is exceptional! I love the challenge and the process of the build. I will not be in any type of hurry at all. Researching, designing and customizing really keeps me in my “happy place”. I’ve got my MK4 and a new Z to drive...

My MK4 was a basic kit, but 90+ of the parts were new, so sourcing the Corvette donor parts will be my challenge. I want to go with the Mendeola transaxle and a new LS7. Maybe the Infinitybox...

Chris

RR46

11-15-2020, 11:53 PM

RR46

11-15-2020, 11:55 PM

The members on the Forum are awesome and there is some extreme talent and innovation. The GTM group is exceptional! I love the challenge and the process of the build. I will not be in any type of hurry at all. Researching, designing and customizing really keeps me in my “happy place”. I’ve got my MK4 and a new Z to drive...

My MK4 was a basic kit, but 90+ of the parts were new, so sourcing the Corvette donor parts will be my challenge. I want to go with the Mendeola transaxle and a new LS7. Maybe the Infinitybox...

Chris

Get your Mendeola order in early, takes a while. Will be well worth it to not worry about blowing up a $10-15k G50 when you unleash the LS7.

cgundermann

11-16-2020, 07:54 AM

So I heard, thank you!

Chris

Shoeless

11-16-2020, 10:39 AM

I second that. I waited two and a half years for mine, but it is a work of art, so I'll give them that.

cgundermann

11-16-2020, 12:09 PM

Did ya all order your Mendeola through FFR or through them?

Chris

crash

11-16-2020, 12:36 PM

A Mendeola Transaxle can only be ordered through Mendeola directly at this point.

Contact Ian @ 619-xxx-xxxx

Sorry, the number has changed...

619 947 6534 ex110

cgundermann

11-16-2020, 02:50 PM

Thanks Crash, tried it but no worky...

I’ll try emailing him.

Chris

crash

11-16-2020, 04:10 PM

Thanks Crash, tried it but no worky...

I’ll try emailing him.

Chris

Number has changed. I updated below...

cgundermann

11-16-2020, 05:04 PM

Thanks crash,

Chris

cgundermann

11-16-2020, 07:47 PM

Number has changed. I updated below...

Crash ~

I’d always heard of the tranny delay, out of curiosity - what’s the reason for the lag time for production? I’m not in a big hurry (lots a balls in the air, e.g. - homes selling and steel shop built), but was wondering...

I’m guessing the virus has taking the wind out of FFR’s annual winter sale.

Chris

crash

11-17-2020, 11:52 AM

Crash ~

I’d always heard of the tranny delay, out of curiosity - what’s the reason for the lag time for production? I’m not in a big hurry (lots a balls in the air, e.g. - homes selling and steel shop built), but was wondering...

I’m guessing the virus has taking the wind out of FFR’s annual winter sale.

Chris

In speaking with Mike and Ian, it sounds like the biggest hurdle is the castings. Pretty much every time they do a run of castings they are spoken for almost immediately. The castings seem to be the part that is the most tricky to build as not only do the parts have to be cast, but then there is quite a bit of machining to be done before they are usable. Also, inevitably with cast materials, there are always parts that look just fine but are eventually rejected because of porosity, a mistake in machining, etc. The lead times are not short on the castings, especially because foundries are really getting hard to find these days, and then you really have no idea what the total usable parts are going to be even if the foundry delivers the requested number of cases/parts.

I believe last time we spoke about this one of them said that they were having to go quite a distance to use a decent foundry. At least Los Angeles, which is a couple of driving hours away from San Diego. This distance makes things more difficult as well.

Any gearbox is really like a watch on the inside and takes some time to get "just right" but I believe the bottleneck in the process is the castings.

Shoeless

11-17-2020, 12:08 PM

crash seems to be spot on here and its the same thing in the aerospace world. Castings are long lead and if they have internal defects that only get exposed by machining and can't be reworked/repaired, than its scrap and you start over.

Personally, I wanted to order one box of everything (Transaxle, Clutch, Flywheel, 930 CVs, Bolts, Support Bearing, Starter,...) that I would need to install this in my GTM. I have honestly only needed to buy different length flywheel bolts and one starter bolt as that one was supposed to be a donor part (hell I probably have it someone in my donor crates of parts).

Once I received the transaxle, it went right in, and Ian has been Johnny on the spot with answering my installation questions. I'll have more questions soon once I'm about to fire up the engine for the first time.

HerculezJT

11-17-2020, 02:46 PM

cgundermann

11-17-2020, 03:29 PM

Thanks Gentlemen - interesting! I’m glad to hear about the great customer service. I’ve been really busy trying to read everyone’s build threads...

Chris

cgundermann

11-17-2020, 03:31 PM

if only you could get one of these
http://supercarsystem.com/gearbox/

Latest Facebook post about this was October 3rd with what seems like good news
"Who wants HYPERDRIVE ? bench testing complete, next stop 7 production units testing including in our own cars and the shockingly talented Cody Loveland dropping Hyperdrives into a couple of Ultimas.
Expect an amazing price around $12k and Q2 2021 delivey! for this aerospace quality 6 speed quiet helical sequential, mass centralized with adjustable ratio rear end and our massive solenoid shift for bump or paddle precision. Those sloppy cables are gone! Oh and yes its pretty."

I remembered seeing that when they first posted info...way, way cool and what a great price point!

Chris

crash

11-18-2020, 11:06 AM

if only you could get one of these
http://supercarsystem.com/gearbox/

Latest Facebook post about this was October 3rd with what seems like good news
"Who wants HYPERDRIVE ? bench testing complete, next stop 7 production units testing including in our own cars and the shockingly talented Cody Loveland dropping Hyperdrives into a couple of Ultimas.
Expect an amazing price around $12k and Q2 2021 delivey! for this aerospace quality 6 speed quiet helical sequential, mass centralized with adjustable ratio rear end and our massive solenoid shift for bump or paddle precision. Those sloppy cables are gone! Oh and yes its pretty."

I would be exceedingly wary of any solenoid shifted unit.

We have all heard before about the latest and greatest that is scheduled to come out, and some even make it to production. None that I have seen live up to the hype.

On the flip side, Mendeola has over 10,000 transmissions out in the world doing what they are supposed to do. This number was told to me during a conversation I had directly with Mike Mendeola.

HerculezJT

11-18-2020, 11:58 AM

I would be exceedingly wary of any solenoid shifted unit.

We have all heard before about the latest and greatest that is scheduled to come out, and some even make it to production. None that I have seen live up to the hype.

On the flip side, Mendeola has over 10,000 transmissions out in the world doing what they are supposed to do. This number was told to me during a conversation I had directly with Mike Mendeola.

Agree that the solenoid is a failure point that sees high amount of use, looking at the CAD however appears to be easy change, cost is unknown. Electronics to control it is also unknown.
By no means am i knocking Mendeola, but nor does it mean any other competitor can't get their claws into the market. Though, per their website, this should have been out in 2018 at around 15K. I look forward to seeing real world results that is not published by the manufacturer. If it does come to fruition with most/all they promised to be, at 12K appears to be good value and gives builders more options to look at.

crash

11-18-2020, 12:15 PM

I was not referring to long term robustness of a solenoid, although that may be an issue, I don't know. The problems I have seen with solenoids are that they are not "soft" like a pneumatic actuator. They tend to damage things within the transmission and also have issues with changing parameters due to heat soak. Springs can be added to soften how the solenoid interacts with the other bits, but the heat and associated electric issues still remain. At some point one adds all this "stuff" to the equation and it just gets out of hand.

I have actually experienced first hand many of these same problems with pneumatic systems, but they do seem to be a little less prone to issues.

Personally, nothing beats a physical shift lever for feel and driver adaptability should a situation arise. This is why we have resisted the "latest and greatest" paddle or electronic shifted options on the FFR PDG GTM race car. For us, in extreme endurance racing situations, the simple beats out the more complex every single time.

Presto51

11-18-2020, 12:40 PM

if only you could get one of these
http://supercarsystem.com/gearbox/

Latest Facebook post about this was October 3rd with what seems like good news
"Who wants HYPERDRIVE ? bench testing complete, next stop 7 production units testing including in our own cars and the shockingly talented Cody Loveland dropping Hyperdrives into a couple of Ultimas.
Expect an amazing price around $12k and Q2 2021 delivey! for this aerospace quality 6 speed quiet helical sequential, mass centralized with adjustable ratio rear end and our massive solenoid shift for bump or paddle precision. Those sloppy cables are gone! Oh and yes its pretty."

Anyone remember the Griffin transaxle that was supposed to give Mendy a run for it's money? https://griffingearboxes.com/

AFAIK still waiting.

Plus it might be faster to either wait for C8's to gather in the salvage yards, or adapt a 7 speed PDK to go in your project, If you really want to have proven paddle shifting. :rolleyes:

Ron

cgundermann

11-18-2020, 03:30 PM

I’ll be plopping down 5K for the Mendeola unit preorder before I order a GTM. I’ll be manual shifting this car. This will be my first transaxle super car and I’m really curious how well this compares in terms of traction with my Cobra. I actually for the first time bought a new paddle shift car recently (something I swore I would never do) - last year of the 370Z with GTR paddle shifters. Was born in Japan and learned to drive on a 280Z, so I have a soft spot for JDMs. The only reason I did (have the stick Cobra) - was because of all the seat time sim racing and grew to like paddle shifting somewhat...for speed.

But, I do subscribe to the KISS principle (keep it simple stupid) especially with a new build platform.

Chris

crash

11-18-2020, 04:33 PM

Sorry Shoeless...we kind of took over your thread.

Let's get back to your awesome build!

Shoeless

11-18-2020, 05:25 PM

No worries fellas for the additional discussion :cool:

Chris,

I did the same and ordered my Mendy before I even ordered my GTM kit. Allbeit only a few months before, but I did order it before my kit. I also ordered my InfinityBox system right at new years time and they were running a really nice special something like 17% off for the end of 2017. I ordered up every component I needed at that time and saved a boat load. Then I realized I would use the inCoder here recently. Not sure if they do this every year, but something worth keeping an eye out for.

cgundermann

11-18-2020, 05:40 PM

Thanks for the tip, I have also thought about the InfinityBox system.

Shoeless

11-26-2020, 08:10 PM

Happy Thanksgiving everyone!!! Hopefully you all got some time on your builds.

I worked on finishing up the CF Intake over the last couple days. I needed to install ports for one of the engine breathers and an Inlet Air Temp Sensor. I broke down and masked up the two pieced of the intake I needed to cut holes in and started to drill progressively larger holes. Once I got closer to about 1/2" drill bit it would almost splinter and catch and want to split the CF sheets so I had to take it VERY slow. Once it started to do this, I shifted over to a rotary file and small sanding wheels with the Dremel to open the holes to the final size. Scuffed up all the parts, cleaned them very well, and used 3M Panel Bond to seal in the pieces I needed. I made a small aluminum support that I hit with 1000 and then 2000 grit sandpaper to give it a nice brushed look.

https://i.imgur.com/z0yqfYw.jpeg

https://i.imgur.com/rPg6qcL.jpeg

https://i.imgur.com/3o0QIei.jpeg

https://i.imgur.com/BPcVeqU.jpeg

https://i.imgur.com/5XK6lmD.jpeg

https://i.imgur.com/FihwNtC.jpeg

https://i.imgur.com/Pl6bXpv.jpeg

crash

11-27-2020, 11:24 AM

Shoeless

11-27-2020, 11:38 AM

Looks really amazing.

One suggestion? Upon final install you might consider rotating the hose clamps so that only the band is showing. Just a little detail that would clean it up a bit. Would probably make them more difficult to access, but IMHO would be cleaner looking.

Hey Crash, thanks for the compliment and I like the idea of rotating the hose clamps so only the band shows. It's the little details that will make this really stand out, so thanks for the input and yes, I bet it will be a PITA LOL.

Just installing the aluminum brace to hold it up had me contorted in all kinds of funny ways, but the overall look is bad a$$ and I love it.

I'm seriously considering Shane's rear hatch piece that has the Lexan see through louvers so you can peek in and see the engine bay detail with the hatch still closed, and having the functionality of allowing hot air out.

crash

11-27-2020, 01:08 PM

Where did you source your "Adel Clamps" (least wise that's what we call them) that are holding down your hoses? We had a stock of those that are almost used up and I am having a tough time finding replacements. I really want to stay away from the plastic versions which I can find easily on the internet.

Shoeless

11-27-2020, 01:33 PM

crash

11-27-2020, 01:46 PM

Shoeless

11-27-2020, 02:14 PM

I must admit it has been a little while since I searched.

Quick search turned up that Jegs has these available...

https://www.jegs.com/i/QuickCar+Racing/635/66-860/10002/-1?msclkid=454d0d347c1019bedc1a52f534c908c6&utm_source=bing&utm_medium=cpc&utm_campaign=BSC%20-%20Non-Brand%20Searches%20-%20Long%20Ship%20Time&utm_term=4579672090658088&utm_content=Other%20Categories%20-%20LST

Looks legit enough for me to use. I know Pegasus has some, a bit pricier though. I had to get a specific size once to hold my new ebrake cables in place and ended up getting a pack of like 5 off Amazon that had good ratings.

beeman

11-27-2020, 08:16 PM

Amazon has a bunch 20% off today for Black Friday, just search for p-clamps.
Great work on the intake, Sean. I'm on Sanibel with the fam this week, hope to make some GTM progress soon.

Shoeless

11-28-2020, 06:22 AM

Great work on the intake, Sean. I'm on Sanibel with the fam this week, hope to make some GTM progress soon.

Thank you Sir!!! I’m looking forward to hearing about your first engine start soon.

Keith1

12-12-2020, 11:23 AM

Shoeless

12-13-2020, 11:40 AM

Awesome work Shoeless, the CA intake turned out great. Your engine bay is so clean and organized. Truly a work of art! For what its worth, I like the clamp screws just the way they are. They add detail in a beautiful engine bay and its functional.

Thanks Keith1!!! The theme I'm going for is really starting to come together. I can't wait to get the engine harness built and laid in place. I'm working on creating pig tails with all Deutsch AS connectors for all the sensors as we speak. VERY time consuming.

Shoeless

02-03-2021, 09:43 PM

Pretty big milestone on the GTM today. So not so fun story that started me down this path a few days ago. So I was test fitting the harness I have been building lately on the GTM and working around the power and ground distribution blocks I have behind the passenger fuel tank. The goal was simple enough, how long do these leads need to be? So as I was wrapping the ground cables around, bam, one of them touched the hot +12V lug and sparks flew. All the excitement, all the anticipation...and I made a stupid mistake like this. My main concern was obviously that I just fried my ECU. My stomach sank. After disconnecting the battery, I pulled the harness and looked over everything VERY carefully. I found no issues and basically concluded one of the leads was grounded somewhere and then I inadvertently hit the power lug. The only outstanding issue was the harness was connected to the ECU at both main connections.

The only thing I could do was push forward with the main bulkhead connector on the harness that would allow me to connect the engine harness to the chassis harness, fire the system up, and ultimately test the ECU. I was able to accomplish this task tonight and confirmed the ECU is just fine!!!!!! I was able to load the latest firmware and actually load one of the base tunes that Infinity has for an LS3 58x timing motor. The instructions state this is good enough to get the engine running, but I still need to make several changes in the configuration setup based on my application.

I was pretty much on cloud 9 knowing I didn't fry my ECU so I took it one step further and pulled out the CD-7 Digital Race Dash. They state this can be powered off the CAN network, but I have seen several people run into an issue with that and opted for simply wiring to 12V switched power. I pulled some new wiring, plugged it in, and bam she fired right up.

https://i.imgur.com/dzvlzd5.jpg

https://i.imgur.com/PShfGgs.jpg

VRaptor SpeedWorks, LLC

02-04-2021, 09:26 AM

Congrats! That is always a great milestone....to wire for days or weeks and then finally hook up power and find out that things really work like you planned! Awesome!!

beeman

02-04-2021, 10:39 AM

Great update, way to keep at it!

RR46

02-04-2021, 12:56 PM

That steering wheel button setup is really neat

Shoeless

02-04-2021, 04:26 PM

Thanks for all the kind words guys!!!

That steering wheel button setup is really neat

This is a custom one off design that I worked up, CNC cut out of carbon fiber, and then clear coated. Took a lot of planning, but turned out awesome!!!

Ajzride

02-04-2021, 09:35 PM

I smoke the ECU on my 818 build, I know that feeling. Looking awesome for you, hope to be seeing the first start video soon.

Shoeless

02-07-2021, 03:13 PM

I smoke the ECU on my 818 build, I know that feeling. Looking awesome for you, hope to be seeing the first start video soon.

OUCH. Yea that sinking feeling haunted over me until I fired it up and confirmed all was well. Thank you for the kind words, the first start is right around the corner, I'm so excited I can hardly sleep.

Shoeless

02-07-2021, 03:18 PM

It's getting closer and closer to the first start. I topped off all the fluids, installed the harness, and am starting to work through the configuration of the ECU.

Thanks to Shane for helping me with the volume of the coolant system (4.5 gallons). I originally picked up 3 gallons and she drank that up no problem LOL. Grabbed a couple more gallons today and I'm sitting right at 4 1/4 gallons with the rear expansion tank about 1/2-3/4 full. I figure I have some air in the system so once I get her up and running we'll revisit this coolant level and make sure she is topped off properly.

https://i.imgur.com/cnYKacx.jpg

VRaptor SpeedWorks, LLC

02-08-2021, 09:37 AM

Shoeless

02-08-2021, 10:32 AM

I would try to purge most of the air out of the system before you start it. I made a quick and dirty "cap" for the coolant reservoir that I hook up to a vacuum brake bleeder. Make sure the tank is about 3/4 full, apply vac for 10 seconds or so, then slowly release the vac to avoid allowing it to suck air back in.....repeat several times until you stop hearing bubbles come up when you vac. Be sure to also purge the air from the top of the radiator.

142262142263

Hey Shane,

Thanks for sharing your tricks of the trade on the vacuum pump setup. This is easy enough for me to slap together.

The wife was nice enough to help me on the top of the radiator side. I have one port blocked off and a pet **** on the other. Once the fluid level came up to the point of dripping out, she closed it off. She is not one to be keen on helping on the GTM build LOL.

VRaptor SpeedWorks, LLC

02-08-2021, 03:14 PM

LOL....apparently the forum does not like the word petcock?

Shoeless

02-08-2021, 04:32 PM

LOL....apparently the forum does not like the word petcock?

HAHAHA now that's funny. I needed a good laugh after this starter motor fiasco.

beeman

02-09-2021, 11:38 AM

She is not one to be keen on helping on the GTM build LOL.

That's not unique to her!
I was recently doing a compression check on my Lotus Esprit, asked my wife to come out to the shop to run the ignition...long story short, I wired in a momentary button to the starter relay so I could get moving on the project!

LOL....apparently the forum does not like the word petcock?

https://64.media.tumblr.com/7b043c7c06ac3579ed2cd4e4c2044432/tumblr_nnhwg5pyus1s7cb35o3_400.gifv

Shoeless

02-09-2021, 04:52 PM

that's not unique to her!
I was recently doing a compression check on my lotus esprit, asked my wife to come out to the shop to run the ignition...long story short, i wired in a momentary button to the starter relay so i could get moving on the project!

https://64.media.tumblr.com/7b043c7c06ac3579ed2cd4e4c2044432/tumblr_nnhwg5pyus1s7cb35o3_400.gifv

hahaha

Shoeless

02-15-2021, 11:13 AM

So today I was gifted another "paid" furlough day from the office. So the efforts continue as I inch closer to firing this beast up. I first started off by grabbing a spark tester to confirm my wiring to each coil. Crash mentioned I may need a resistor between a couple of the contacts, so I'll leave the boots off the coil connection side of the harness for now. I went coil by coil and validated that I do have spark for each one, so not sure if I will need this resistor or not. Hopefully Crash will chime in with more details, but I understand it being many years ago, the details behind it may have been lost.

The second task was to start digging in and learning the ins and outs of the AEM CD7 Digital Race Dash and how to actually design and make changes. I won't go too in-depth on the design side just yet, but I do want to make several changes to current layouts. AEM was nice enough to create videos to help familiarize everyone with this dash and they were very helpful. I started off with making changes to the main home screen I'll use most often. I needed to add Fuel Level and was able to do this through the 6 port CAN expansion hub and put that right on my main screen. Also needed to add an odometer. I'm hoping I have this one setup correctly with the only issue being it may report out in km instead of miles. There is a test function in the software and I timed it and believe I have it set up properly. Pretty cool that it will take my GPS speed from my Vehicle Dynamics Module. This software is actually pretty simple to pull in additional data off the CAN network.

Now that the main screen is set and I added the odometer, it was time to create a performance timer page. I added 0-60, 0-100, 60 ft, 330 ft, 1/8 mile, and 1/4 mile timers. You can set up all kinds of conditions for it to switch to this screen at the end of a 1/4 mile run. For example, I can set a condition to switch to this page if the car is running 120+ mph and the throttle is less than 1%. This simulates the end of a 1/4 mile run on the track and will display all the performance data.

I was also able to set up Alarms and Warnings. Warnings will show up on the bottom of the screen in red and an Alarm will switch to the Alarm page. You can see a few already showing up as I have a few sensors disconnected and a few I need to change the conditions. Warning

https://i.imgur.com/7VknIYU.jpeg

https://i.imgur.com/ch3WuH9.jpeg

https://i.imgur.com/4RMq68x.jpeg

https://i.imgur.com/FfpamjG.jpeg

crash

02-16-2021, 03:36 PM

I did get some pics for you...142799142800

Shoeless

02-16-2021, 08:43 PM

I did get some pics for you...142799142800

Thanks for sending these over. If my color coding is correct they look like 1,500 ohm resistors and going from your first to fourth pin of the plug. From your comment on bleed down this looks to be from the +12V switched power to ground.

Do you mind if I ask why kind of coils those are?

crash

02-17-2021, 11:28 AM

I will check which pins and get you a coil part number later today.

Shoeless

02-21-2021, 06:03 PM

As I'm prepping Shoeless GTM for first start next weekend (fingers crossed I fire it up on 2/27, one day before my bday), I figured I would share about my journey in trying to tune this bad boy myself. Ideally, I wish I could simply rent time on someone's dyno and work on the tuning myself, but I'm not betting many people will just turn me loose with their shops equipment. Maybe I'll get lucky and find someone that will at least let me be part of the process, but first I'll get it up and running on my own, get the alignment done, and start road tuning myself. In the end, even if I'm happy with how its running, there are few ways to get around a load bearing dyno that will hold you at contact RPM for steady state tuning to really maximize timing and MBT (max break torque).

So let's start this off. I'm running a BluePrint Engines LS3 / 427 that is bored and stroked and came with a dyno sheet on a GM computer with 625 hp and 595 ftlbs of torque. The drawbacks to this was if I stayed with the factor computer I would have to pay or build a harness that would be GTM specific and I wouldn't have all the cool options that I wanted in this build (traction control, launch control,...). So I opted to run an AEM Infinity Series 7 ECU and from my other thread, build my own engine harness. With that said, I'll be following the training I took at HP Academy on the tuning and will gladly share all the details along the way.

Step one is ECU Configuration and Testing. The AEM software as a Setup Wizard that make this step pretty easy. Worth nothing is this should be done connected to the ECU and having it powered up. The first tab is for choosing the Engine. Since the AEM software already came with a preconfigured LS3 58X Timing Engine, and this is the file I started with, most of this is already setup, but needs confirmation. Displacement, Ignition Type, Firing Order, and most importantly VE (Volumetric Efficiency) tuning. This is what will allow me to run this setup without the standard Mass Airflow Sensor as the system is now set to VE and will use MAP pressure in kPa as the load axis for main spark and VE tables.

https://i.imgur.com/kWIRfWI.png

Next is confirming this is a 58X timing engine setup for the Cam/Crank setup. When I was originally planning out my harness AEM had a schematic for a 24X engine and were kind enough to provide the secret sauce of what pins to change on the Cam sensor to make it a 58X setup.

https://i.imgur.com/CJzj985.png

Next is the Injector setup. The first item to choose on this tab is the Primary Fuel Pressure Regulator Reference. If you are using a returnees system, you simply choose Atmospheric Reference. Next up is choosing your injector. The infinity software has plenty of injectors to choose from and after some cross referencing some part numbers, I discovered I have LS7 Injectors. You then choose the Primary Injector Duty Limit, with 95% being safe. By choosing this preconfigured injector, the software sets up flow rate based on fuel pressure, injector offset timing, and offset table.

https://i.imgur.com/znQWHTp.png

Next up is Basic Sensor setup. This table lists the standard common sensors, the channel they are operating on, pin location on the harness, and raw and scaled data. Note there are no scaled values here showing up, as I took this screenshot not connected to the ECU, but if I was connected it would show the actual values. From here you can double click on each sensor and actually make several changes if needed. For example I'm running Bosch PST-F 1 Combined Pressure and Temperature Sensors for both Fuel Pressure/Temp and Oil Pressure/Temp. When I double clicked on these pressure sensors to configure them, AEM only listed a couple options (AEM 100psi and AEM 150psi). After a "phone a friend" to the AEM FaceBook page, a guy confirmed choose the AEM 150psi is the proper option for the Bosch PST-F 1 to work properly.

https://i.imgur.com/SwhWbMg.png

Next up was setting up the DBW pedal. The software has a simple 5 step wizard that gives you directions and actually calibrates your actual pedal to the DBW Throttle Body and after a few clicks, this was done. I did bump the Idle Control Range down from 15% to 10% as there will be other idle controls working in the background and wanted to see if I can get away with less pedal action. I'm also running a 90 mm throttle body, so we'll see how this works out.

https://i.imgur.com/Ro6PZZM.png

At this point, you can click through the tables, starting on the Dash table to see if the sensors are operating properly. The throttle % is at 10% as expected from the DBW tab, Air Temp, Battery Voltage, Coolant Temp, and MAP are all reading properly. There are a few other "Engine Protect" states listed on the top right. All reporting back 0 is indicating there are no protections active.

https://i.imgur.com/f6ji7Dj.png

At this point Step 1 is complete and next up is Trigger Setup. If I get some time tonight, I'll give the write up on that.

crash

02-22-2021, 11:31 AM

Shoeless

02-22-2021, 05:52 PM

I looked a little closer this weekend and took some pictures. Of interest is that there is a jumper on the black wire that combines the black pin with the one next to it, and then the detail on the resistor shows that it is in fact not jumped to the red wire on the end, but to the pin next to the red wire.

Very interesting. I tried looking up diagrams for this coil PN and couldn't locate anything definitive, I may have to look more later. For the typical 4 plug coil you have Switched 12V, Coil Trigger, and two variations of grounds. My coils run a sensor ground and a battery ground, others run a battery ground and a ground that is supposed to be a short lead ground to the cylinder head, and others I see are both grounds can go to chassis ground. Looks like yours is the last one. I'm scratching my head on the resistor now knowing that it is going from your trigger wire to ground. I wonder if this has something to do with the type of ECU you are running and it requiring some type of workaround to get it to trigger these types of coils properly?

Shoeless

02-22-2021, 06:14 PM

Step 2 is Trigger Setup. I touched on it in Step 1 a bit, but choosing the Cam/Crank trigger tab allows you to choose the Sensor Selection. For GM LS you have either a 24X of 58X engine.

The next step is to test to see if the ECU is receiving the signals from the Cam and Crank sensors and what is the probability that the engine will fire up. If you click on the Coil / Injectors tab you can turn off all the injectors and coils so that when you crank the engine these will not fire.

https://i.imgur.com/rCbKYP6.png

Now that the Coils and Injectors are turned off, pull up the Diagnosis tab and you are looking for a few items. Most importantly to me at the moment is Sync State and Start Probability, but there are other parameters you need to pay attention to here as well. Engine Speed - You want to see this in the 150-300 RPM range and you want it to be stable and not seen on this tab, but you can add, is Oil Pressure. I pulled this up on my CD-7 Race Dash so I could keep an eye on it while cranking.

Now crank the engine over. After a stable RPM is reached, I see 50 psi of oil pressure, and my Sync State changes to 1 and green and the Start Probability goes to 100% and green. The ECU is now confirmed that it is receiving the proper signals to actually run the engine.

https://i.imgur.com/LpCQdwJ.png

Step 2 is complete, I can turn the injectors and coils back on and can go on to step 3. Before I moved on, I wanted to confirm my coil wiring, so I picked up a spark tester and tested all 8 coils. Sure enough all 8 coils are firing and I can move on to Step 3 which is Base Table Configuration.

beeman

02-22-2021, 08:38 PM

Cool stuff, Sean, thanks for sharing your knowledge

Shoeless

02-22-2021, 09:01 PM

Cool stuff, Sean, thanks for sharing your knowledge

Thanks Dave!!! I'm really enjoying the whole process of learning about this stuff, applying it to my build, and sharing with the group here.

Shoeless

02-22-2021, 09:39 PM

Step 3 is up next and will be focused on Base Table Configuration. Just like what has already been shared about the AEM software, there are base tables available for an LS3 58X motor, but it is fully understood that they are only good enough to get an engine running and get it straight to a tuner. I'll share the tables and I'll highlight a few issues I see with them right off the bat and what changes should be made to make it safe for me to fire my engine up this weekend.

At this point we don't need to be exact. This is something I'm told lots of people try to spent too much time perfecting before even getting the engine running and you really shouldn't. Also for these base tables there is way too much fidelity and I'll be removing it. What I mean by fidelity is there are load zones every 5 kPa on the vertical load axis and its not needed. The software will interpolate between cells and having to populate a table of this size is just not needed. What is needed is to have additional fidelity around idle and cruise areas.

First up is taking a look at the VE Table. Again way too much fidelity and for starting a tune we need to start with something different. We will tune this table later based on the target Lambda that we choose for each area of that table.

https://i.imgur.com/VA6Z8jT.png

Next table is the Ignition Table. Once again too much fidelity and there is a little too much timing in this overall table to match my engine. BluePrint was nice enough to give me a tag on my engine stating that initial advance for my engine should be 13-16 degrees BTDC and the total advance should be no more than 34 degrees BTDC and should be reached by about 4000 RPM. This could mean a few things. Most important is, this engine may be knock limited and while I'm tuning I need to be running quality knock detection equipment (I planned on this anyways) to stay away from knock. When I say "knock limited" it means there will be point in the tuning process where timing is being pulled out as you are trying to reach MBT (max break torque), but all the sudden run into a knock condition and you have to add timing back in to no damage the engine. There are other engines that you can pull as much timing out as you want, go way past MBT (counter intuitive to max torque), and not have to worry about knock. So either this engine is knock limited or maybe this is BluePrint Engines way of protecting themselves a bit. Regardless, we'll find out.

https://i.imgur.com/ce2GJam.png

The third table we'll review here is the Lambda Target Table. Lambda is a factor number of stoichiometric number and another way to tune things. For gasoline the stoichiometric number is 14.7 to 1 and has a Lambda value of 1. Lambda values < 1 are richer and Lambda values > 1 are leaner. Lambda is used as an easier means for tuning as when you have to take out say 5-8% of fuel from the VE table to run at the large Lambda, the numbers are just easier. Could issues with this table. if you look at the 3D graph off to the right, it has peeks and valleys all over and is not really smooth. The target Lambda numbers are not far off from each other, but the table is not smooth. So when you are transitioning through different areas of this table the target Lambda are all over. We'll address this. Also, since I'm not running a boosted application, the 105 kPA row can be removed.

https://i.imgur.com/JtrBedN.png

Step 3 To Be Continued....

crash

02-23-2021, 12:56 PM

Very interesting. I tried looking up diagrams for this coil PN and couldn't locate anything definitive, I may have to look more later. For the typical 4 plug coil you have Switched 12V, Coil Trigger, and two variations of grounds. My coils run a sensor ground and a battery ground, others run a battery ground and a ground that is supposed to be a short lead ground to the cylinder head, and others I see are both grounds can go to chassis ground. Looks like yours is the last one. I'm scratching my head on the resistor now knowing that it is going from your trigger wire to ground. I wonder if this has something to do with the type of ECU you are running and it requiring some type of workaround to get it to trigger these types of coils properly?

I was thinking the same. It is a Life Racing F88 ECU. Sorry I can't be of more help. It was a long time ago.

Shoeless

02-23-2021, 01:50 PM

I was thinking the same. It is a Life Racing F88 ECU. Sorry I can't be of more help. It was a long time ago.

No worries at all. I appreciate you take a look back as it helped me relook at my setup to see if I was missing anything. I don't have much time to spend learning another ECU at the moment, I'm staying plenty of busy getting ready to fire mine up this weekend :cool:

Shoeless

02-23-2021, 07:30 PM

Step 3 Continued....

Before I jump into adjusting tables, I thought it would be a good idea to share an AFR Target Table and discuss all the regions. The x-axis is Engine RPM and the y-axis is engine load as MAP.

Idle and Cruise is where we will spend 95% of our time as a road car and the overall goal for this areas is smoothness of engine operation and fuel economy. An unmodified engine will operate happily with a Lambda of 1 in this region. Larger displacement engines such as our LS motors can perform smoothly with a lambda of 1.05, but you could go richer at idle, closer to a lambda of 0.95, because if it's tuned to lambda of 1.0 it could present a lean condition after a hot restart. Fortunately, I'm running closed looped lambda control and this step is not necessary as the closed loop control will take care of this

High RPM Vacuum is an area the engine doesn't operate much, really the only situation where you run a high RPM with low throttle position will be during a downshift. In this area of the table we should be targeting around 0.95.

In the Start Up Region the engine will be accessing the cranking enrichment and post start enrichment tables. These enrichment tables will influence start up more than a target AFR or fuel table.

Dead Zones are areas you will not operate the engine in and you simply smooth out the table across these regions using the horizontal and vertical interpolation functions when working on the tables.

Full Load Naturally Aspirated and Transition into Forced Induction is your typical max load region targeting around a 0.9 lambda and you are actually using the extra fuel to control the combustion temperature while you are cranking out max power. At this high RPM operation, the intake, throttle body, and air filter will typically become restrictive and can run engine vacuum down to 90-95 kPa. We need to account for this to make sure the AFR target is sufficiently rich and can go as low as 0.85.

Past this and not applicable for my build is the medium and high boost regions so we'll skip this.

https://i.imgur.com/yFn0vbZ.png

First we are going to work on the Lambda Target Table. If you compare the below table you note it is quite different from the base one shown above. I have targeted a lambda of 1.0 in the idle and cruise, High RPM Vacuum I've placed at 0.87, and made several adjustments in the Full Load region with 0.95 all the way out at what max RPM and 0.85 at that 100 kPa cells. Once these general areas are filled in you can have the software interpolate horizontally and vertically to smooth out the table. The Lambda Target Table is now set.

https://i.imgur.com/V73swsn.png

Step 3 to be continued....

Shoeless

02-23-2021, 09:04 PM

Step 3 Continued....

Now that we have the lambda target table set up we need to return to the Ignition and VE Tables. Starting off with the Ignition table we can actually highlight the entire table and set it to one or two values. Remembering back to what BluePrint Engines tag stated as a safe initial ignition timing of 13-16 deg BTDC, I've elected to use 15 deg. This is a good safe starting point for firing this engine up. In order to make this even more safe and ensure I don't run into any issues up front with knock, I've pulled another 5 degrees out at full throttle low RPM. We always want to start with retarded ignition timing that is very safe and we can advance towards MBT during the tuning process.

https://i.imgur.com/B7eDX0s.png

Next is the VE Table. At this point we don't really know what the engine's volumetric efficiency is, so we are going to start with choosing a value of 50 for the entire table. We know this is not correct, but we can easily and quickly dial this in once we get the engine running. Once we start tuning this table in the idle region, the shape of the table will be able to be carried forward for the overall shape of the table.

https://i.imgur.com/fVwTTRh.png

Step 3 is now complete.

Step 4 is Base Ignition Timing and Base Fuel Pressure. Let's start with Fuel Pressure because I have a returnees system and I can not adjust the fuel pressure. I am running a Lingenfelter High Flow Fuel Pump and it will run at a constant pressure of 58 psi at 13.5 Volts. Side note, I need to wire up the turn on signal to my CTSV Alternator with a Pulse Width Modulated Output. I'm waiting on a pack a resistors to show up and this is literally the very last thing I need to fire the engine up for the first time. Even though my fuel pressure will be constant, it is very beneficial to run a fuel pressure gauge as it will indicate if I have a problem with the fuel system before I get into tuning and waste valuable time if I am actually on a dyno. From here you can take a look at the Injector Tab. Since I was able to choose LS7 Injectors, this Table was completely filled out for me. The InjFlowRate Table is a 2D table that is running differential pressure (delta between pressure in the inlet manifold and the fuel pressure). So when there is a delta in this pressure, this is how the ECU will be compensating. Same for InjectorOffse table. Depending on battery voltage and differential fuel pressure, the offset will change.

https://i.imgur.com/5xXqiG9.png

Next up is checking the base ignition. This step could be easy to overlook, and could have serious consequences if skipped and the timing is actually off. In summary this step is validation the timing of the engine against what the ECU thinks the timing is. If the engine is seeing less timing, it's not too bad, but if it's more advanced that we think it is, it could cause knock.

I had to jury rig up a timing pointer, find TDC on the engine and create marks on my timing pulley to validate this. On the Ignition Sync tab there is a check box to Lock Ignition Timing and you can choose the degrees BTDC. By checking this box, it locks the timing across the entire operating environment and no changes are made for start enrichment or other offset. This will allow me to use a timing light and confirm this timing on the crank. If there is a difference, you can click advance or retard under Synch Adjustment. If you can get this within a 3-5 degrees that's fine. Once this matches you can move forward, but you need to check again at higher RPMs once the engine is up and running. The idea is that you can do this while cranking the engine and before attempting to start, but also need to validate at around 2,000 RPM.

I went out and picked up a super nice digital timing gun, hooked it up, cranked the engine over, and nothing. Dang it. So I referred back to the instructions manual and sure enough, it won't operate at RPMs under something like 400. So me cranking the engine at 250 ish RPM is not activating the timing gun. What I'll do is check this block and lock the timing for the first fire up and check timing nearly immediately once I ensure the engine is running safely.

https://i.imgur.com/Qx2XiB3.png

Step 4 is now complete.

Step 5 Initial Start up is next. Finally, after 3 years and 4 months of effort, I will be attempting to fire this bad boy up this Saturday morning. I do not anticipate it will idle well and may need to use some throttle to keep it running. During this initial fire up, I'll highlight all the cells in the VE table that I'll operate in during this initial start and can use hot keys for course changes. What I'll be looking at is the target lambda and what it is actively measuring.

Shoeless

02-27-2021, 06:42 AM

One last item to knock out this morning was wiring up the alternator. Easy enough, but I have the newer CTS-V that requires a PWM signal to operate properly. Thankfully the AEM makes this very easy to kick out a 128 Hz 60% duty cycle signal. Just needed to wire up a pull up resistor on a +5V sensor power output. Note this one of only a few areas you should be using solder in any wiring harness.

https://i.imgur.com/B3KELoW.jpg

https://i.imgur.com/Vkun6ca.jpg

From here I needed to go back into the AEM software and make some changes. First off was configuring this Output. Lowside Switch 7 is set to general purpose output and then on the output tables you can see the frequency at 128 Hz and then you set the whole 2D table to 60. I can actually change the duty cycle and therefore change the alternator output depending on Engine RPM and Battery Voltage. For now we will keep this whole table at 60 to make sure its working when I fire the motor up.

https://i.imgur.com/DMBOftd.png

https://i.imgur.com/jCdhLq2.png

Shoeless

02-27-2021, 01:45 PM

Today was the day, GTM #501 is alive. Time to start working on the idle tuning to get it firing up and running smooth before moving forward. Also at the point I could likely remove the harness soon and install all the final shrink moldable boots.

https://youtu.be/7V6es9w0X3g

KGTM

02-27-2021, 03:05 PM

Congratulation.

VRaptor SpeedWorks, LLC

03-01-2021, 09:15 AM

Congrats on the start-up! Sounds great!!

Shoeless

03-01-2021, 11:35 AM

Many thanks fellas!!! I was totally not prepared for how NICE it would really sound.

I’ve pulled the harness and have started to shrink all the boots and seal it up to make it a finished product. This should take a bit as I can only do so many at a time as they need to cure overnight. Once that is complete is will go back in for the last time and I’ll get started on the idle tuning. AEM has made a few detailed videos to go by so that’s helpful.

crash

03-01-2021, 02:15 PM

Such a rewarding milestone. Congrats.

Shoeless

03-02-2021, 08:03 AM

Such a rewarding milestone. Congrats.

Thank you Sir!!!!

beeman

03-02-2021, 08:13 AM

Congrats on the 1st start! Even more impressive with the custom harness and standalone ECU.
Quite an audience, I don't think I've ever had that many people to my birthday party!

Shoeless

03-02-2021, 10:52 AM

Congrats on the 1st start! Even more impressive with the custom harness and standalone ECU.
Quite an audience, I don't think I've ever had that many people to my birthday party!

Thanks Dave!!!! I'm really enjoying the fact I have done all of this on my own. It has been a HUGE undertaking to say the least, but I'm loving it.

Definitely had quite the audience. Some of these guys have helped on the build (Pull body of or install the engine) and others are car guys that have been following my build. I even got my wifey to hang out in the back and she was quite surprised as well. No pressure on making sure it would actually fire up, LOL. I was rather impressed, 3 turns of the key and the fuel system primed and it fired right up.

Shoeless

03-06-2021, 12:12 PM

Tires arrived yesterday. I decided to go with Michelin Pilot Sport 4S per some recommendations with 245/35ZR-19 for the front and 325/25ZR-20 on the rear. These pics never get old :cool:

https://i.imgur.com/GVFB4SJ.jpg

https://i.imgur.com/t3sNZCr.jpg

https://i.imgur.com/GFxZm4z.jpg

https://i.imgur.com/1fKEKIQ.jpg

RR46

03-06-2021, 11:31 PM

So nice to see a brand new clean build. Also great to hear the LS7 engine sound clips.

Shoeless

03-07-2021, 09:43 AM

So nice to see a brand new clean build. Also great to hear the LS7 engine sound clips.

Thank you Sir, its actually an LS3/427. I will say it should hold its own to an LS7 nicely, simply comparing dyno sheets.

Shoeless

03-14-2021, 04:55 PM

I'm currently working on some idle tuning, but am very restricted on the duration I can run the engine. The GTM's orientation in the garage is as if I backed it in and unfortunately even with some fans running, the carbon monoxide alarms go crazy and the smell is getting into the house, so I'll have to hold off on more tuning until I can get it spun around. I've got a local machine shop making me a steel plug for my rim so I can do the alignment with the caster and camber gauge. Hopefully this will be done on Monday and I can take my rims and tires to be mounted and balanced later in the week.

On the positive side. I did get a few short runs in and got to a decent point where the engine seems to be idling somewhat nicely. At least that's what I though until I pulled the data logs and started to look closer, more on that soon. So let's start off with the Idle Tab in the Infinity tuning software and the Idle tab in the Wizard set up.

https://i.imgur.com/3DOq6wi.png

On the Idle Tab there are several 2D tables that need addressing. The first in the idle calculation in the ECU and the first one to set is the Idle Target Table. You need to choose idle targets from cold start all the way through up to normal operating temperature. After a bit of research I found some specifics that can be used as a guide here and its all based on your cam. If you are running a cam that is between stock and 224 degrees intake duration, an idle target of 800 RPM at normal operating temps would be a good start. If your cam is between 224 and 236 duration on the intake side, 900 RPM might be a good starting point. Finally for cams larger than 236, an idle RPM of 975 would be appropriate. My engine's intake cam duration is 239, so I'm going for 975 as my target RPM at operating temperatures. The article I found also state a cold start RPM should be 100-150 higher than this, but I left it at 1250 to see how it would do.

Idle Base Position is the second step in the idle calculation. Depending on the target idle RPM this table sets the initial open loop idle position that will be used to reach the desire idle RPM. In simple terms if the engine is idling below the target RPM at the given engine temperature, you increase this number. Conversely if the ending is idling above the target RPM at the given engine temperature, you lower this number.

The third step in the idle calculation is Idle Feedback Active. I'll show that in the wizard shortly, but if the engine speed and throttle position meet certain criterial this channel will turn on and the ECU will use closed loop idle feedback to try and get the engine speed closer to the idle target.

There are a few more tables available as well. Idle Target Offset allows for the idle speed to be increased for the first few seconds the engine is running. Idle Decel is a table that allows an extra idle air offset to prevent stalling when decelerating quickly. Ign Trim Idle apples an ignition trim as a function of RPM error. Negative numbers retard ignition and positive numbers advance. The effects of this table are pretty simple. As you advance timing it will tend to increase engine speed slightly and as you retard timing it will slow it down.

Next we'll take a look at the Wizard.

https://i.imgur.com/3HkZmFY.png

https://i.imgur.com/ga4vsoG.png

In the Wizard there are several items to discuss. First is when will idle activation occur. I have this set to idle on with the TPS of 1% and idle on below 2000 RPM. Idle Feedback Min and Max are set to -0.1 and 0.1 as I don't want to have this idle control to be functioning while I am working on the steps above in the idle calculation. Once I get this items above set, then we can work in this area. This feedback is intended to compensate for other condition as when I tune the idle, its only for one day at that specific time.

In the advanced setup portion is the P, I, and D Gains. I learned a simple analogy for these earlier and I think its the best way to describe these. Note, these are very sensitive parameters and can greatly impact idle function. Let's say you are in your car and ahead of you is a check point you need to get to, but not go past (i.e. your target idle RPM). Proportional gain is equivalent to your gas pedal. You want to get to that checkpoint point quickly so you hit the gas hard, but then you realize you overshoot the checkpoint and have to reverse to get back to it. Derivative gain can be thought of as your brake pedal. You can use a lot of throttle to get to the checkpoint quickly, but as you get closer, you need to apply the brakes so you don't overshoot it. If we use P and D gains only, we will get close to the target, but never actually get right on the target. The reason is the closer we get to the target, the effect of the P gain gets smaller and smaller. Integral gain then works to get you right on target.

Idle Feedback Deadband is a bandwidth of an RPM range above and below your target where feedback is disabled. From what I have see so far with my engine and the aggressive cam, I'll likely need to adjust this a bit later.

There are also offsets for is AC or Fans are running.

To be continued....

Shoeless

03-14-2021, 06:55 PM

Continued...

Now we have a basic understanding of the idle functions, how the ECU calculates, and in what order, the idle targets. So let's jump right in. Some of the early starts and running the engine up to normal operating temps involved Idle Feedback turned off and focusing directly on the Idle Base Position table. I ran a few data logs and watched my engine RPM oscillate quite a bit as it was getting up to temp but I was able to adjust this table based on the target RPM and where the engine was running. Again if the actual RPM was low, just increase the numbers for the specific operating temperature the engine is at. You want to run the engine a bit higher than the target to compensate for any load that may turn on (Fans, A/C,.....). The oscillation seemed to smooth out as the engine got up to temp so there are a few things I can do to address that. Let''s look at the log for one of the starts.

Up first is a 3 min run. I ended up stopping the log before getting to full operating temp so I could focus on the early stages of ignition and through early warm up. This was all done at idle with one blip of the throttle to see how it would act.
https://i.imgur.com/apMniAp.png

Top Graph:
There are some main takeaways here. First, right up front where the engine was started (all the way on the left), you can see some of the logic working to control the RPM (orange line) and keep it from stalling, but then goes quickly into an RPM oscillation phase while the engine is heating up. As the engine is heating up the RPM oscillation settles down and less correction is added.

Middle Graph:
This is from the Ign Trim Idle table in the previous post. I have this table set that if I'm above or below the target RPM to add timing or pull timing out to try and settle out the RPM oscillation. Early on in the run there is quite a bit of timing being added in try and increase the engine RPM to get to the target. This settles out as engine gets up to operating temps.

Bottom Graph:
Similar to the middle graph, this is the actual Spark Timing the ECU is commanding. I have my base tables set to 15 deg of timing through the whole idle range, but you can see how the 2D table is advancing the timing.

Let's look at some specific areas of this data log. First up is from ignition to 20 seconds.
https://i.imgur.com/r7oWJpS.png

Top Graph:
During cranking of the engine, the idle target is about 1570 RPM and then steps down almost instantaneously as the engine fires up. Following the orange actual RPM line you can see the engine fire up and go to about 1450 RPM before dropping all the way down to 810 RPM and the settling into an average of about 1000 RPM. The target RPM is following the logic we have on the Idle Tab.

Middle and Bottom Graph:
Right as the engine is turning over you can see a drop to 10 degrees in timing, go right up to 20 degrees, drop out to 17 degrees, and then go 20. So although the engine seemed to turn over pretty nicely, the data shows I have some oscillation. We'll work on that. As the run continues there is A LOT of oscillation where the ECU is adding timing, pulling timing, and then adding timing back in. This is likely happening because of a couple factors, but let's take a look at the obvious one. The actual engine RPM is below the target, then immediately above, and then below again. So the ECU is trying to add and then pull timing out to get to the target RPM, but it overshooting. This may be a factor of the aggressive cam or other factors, but what I need to do is go back and zero the Ign Trim Idle table to zero across the Idle RPM Error range to stop the ECU from trying to make these corrections and fix the Idle Base Position table first. I'm clearly off in the early running and low engine temp ranges, but we'll fix that.

To be continued....

Shoeless

03-15-2021, 11:20 AM

Continued...

Let's take a look at the next area of the log from about 16 seconds out to 1:41. Although not on the plot (I forgot to add it) the temp range for his time period is 80 deg F to about 112 deg F.

https://i.imgur.com/T7yyDcG.png

As we have noted before, this area of the plot is where the engine is heating up and the oscillation of the engine RPM settles down. This could be that I have the Idle Base Position closer to an acceptable level as the engine is heating up. You can see that the Ign Trim reduces as the engine heats up and less correction is needed to hit the target RPM. Looking at the actual RPM range on the right side of the plot, I'm seeing about -50 and +30 range for the RPM compared to the target. This is getting very close to acceptable, but I should bump this up a bit to have an average of about +50 compared to the target.

The last time period we will look at is from 1:20 to about 2:45. The temp range starts at about 107 deg F and goes to about 136 deg F. Still not up to full operating temperature, but there are some things we can infer here.

https://i.imgur.com/d5NRzMu.png

The RPM range I'm seeing here is about 60 RPM and is pretty close to the target RPM. Note the target RPM is tapering down as the engine is heating up. Ign Trim corrections are smaller and the timing spread is going from about 13 deg to 16 deg which is getting to a pretty acceptable level.

I did throw in a little throttle pedal blip just to see how it would look. It was actually a very small tap on the pedal followed by a little higher tap on the gas pedal. It looks like the engine responded very nicely as soon as the pedal was pressed, but maybe a little work can be done on the back side when the engine is returning to a stable idle. Keeping in mind the engine isn't fully warmed up here, so I really shouldn't pay too much attention to this, but it was fun to look at.

Sorry for the longs posts, but I'm enjoying documenting this process, and i hope you are enjoying them. I've got a few other log files, I hope some that I have the engine up to operating temp, but I'll have to take a look at them to see what I all logged.

q4stix

03-15-2021, 02:10 PM

No need to apologize for the long posts! We get to learn more while you learn.
Glad to see you're getting up and running with the Infinity too!

Shoeless

03-16-2021, 07:28 AM

No need to apologize for the long posts! We get to learn more while you learn.
Glad to see you're getting up and running with the Infinity too!

Sounds good to me, I'll keep the posts coming :cool:

I'm really enjoying working in the Infinity ECU, pretty straight forward and user friendly. Although I don't really have anything to compare it to.

Shoeless

03-16-2021, 10:22 AM

I was able to locate the log file that I started at the end of the above file. This log file will continue where the last one left off and go all the way up to engine operating temps of about 210 deg F.

Lets start with looking at the full run. This log is in total about 5 min and 20 seconds and has a number of areas we will zoom in on and discuss.
https://i.imgur.com/FbSk1yM.png

Top Graph:
I've added a couple parameters to the trace as I was interested in seeing more of what was going on (BTW I can go back to any of these log files and pull up what seems like a couple hundred parameters that the engine is logging. You can go in the Infinity software and pick and choose what parameters you want to actually log.). I've added Throttle % and DBW_APP1. The reasoning behind this is I wanted to see where Feedback was activated. Throttle % is higher than DBW_APP1 as the ECU is using the throttle body as a replacement to an Idle Air Control Valve to control idle and I have that set to either 10% or 15%. DBW_APP1 is a parameter from the DBW throttle body and is the number used for if Idle Feedback is active. Essentially if I'm not touching the pedal, the Throttle % will be between 10 and 15 and DBW_APP1 is 0 and this will activate Idle Feedback.

Middle and Bottom:
I've added Coolant Temp in Deg C (I need to figure out how to change this to deg F) so that we can see at what point the engine gets up to normal operating temp (at about the 4:40 mark). I've continued to pull in Ign Trim Idle and Spk Timing as I wanted to see how much of this feedback is happening here while the engine is getting up to temp.

Let's break this down into three focus areas. The first one we will look at is from about 1:40 to 1:48. This is a small 8 second view, but I wanted to see how a blip on the throttle would look as we are getting up to temp. At this point the engine is at 176 deg F and getting closer to normal operating temps.
https://i.imgur.com/Sed2vit.png

Top Graph:
Looking at the green line for Throttle %, I have a little stutter in my pressing of the throttle, but it achieved what I was going after. The target RPM shot up, actual engine RPM increased somewhat smoothly and also decreased back towards the idle target RPM smoothly. Comparing this to the previous blip of the throttle while the engine was colder, this is starting to act more in line with acceptable expectations. You can see on the back side of the throttle blip where timing was pulled out (Bottom and Middle Graph) by the ECU to help reduce the actual RPM back to the idle target. There is a little oscillation after returning to idle RPM, but need to look closer at this to see if it matches the normal oscillation I'm seeing at stable idle.

To be continued....

Shoeless

03-16-2021, 08:07 PM

Continued....

Middle and Bottom Graph:
Picking up from the above you can see where 3 degrees of timing was pulled out as the engine was returning to the target idle RPM on the back side of the throttle blip. Once the actual engine RPM got back close to the target RPM the amount of timing being pulled out is reduced. Following the throttle blip there is still timing being pulled out. The two troughs where its taking out about 2.5 to 3.0 deg of timing, the actual engine RPM is about 100 higher than the target. Once I get some more time on the motor and dial in the idle I'll be able to set an acceptable dead band where no feedback will be activated. We'll work on that soon.

The next area to look at is from 2:30 to 2:36. Engine temps are up to 190 deg in the time band.
https://i.imgur.com/L9ywcYK.png

Top Graph:
Here we have three throttle blips and then I let the engine try to get back to idle. By now our target RPM is 975 and will stay at this rate for the normal idle RPM rate. On the back side of the two larger blips, you can see when engine RPM is decreasing smoothly back towards the idle target. Although on the back side of the last blip, you can see engine RPM goes below the target RPM for a very short period, the timing over corrects and actual engine RPM bumps up to just over 1100 before dropping below the target again. Once again we have a little oscillation and I'll work on that once I can get the car moved around in the garage to run it again.

Middle and Bottom Graph:
On the backside of the throttle blips you can follow where the timing was added to bring up the engine RPM and then taken away when the actual RPM overshoots the target.

The last area we will look at is 4:15 to 5:30 and there were a couple things happening here. By now engine temps are at normal operating conditions at about 204 deg F.
https://i.imgur.com/vIzEUCw.png

Top Graph:
On the left side of this trace, the engine is idling very smoothly with a max RPM of about 1040 and min RPM of 940, with very little timing correction taking place to control this RPM against the target. No more than about 1.5 deg of timing is pulled out at one spot and then no more than 0.6 deg of timing is added in. This is looking really good for once the engine gets up to operating temp so I'm pretty happy here, but I decided to try something on the right side of this trace. I tried changing the target idle to 925 RPM and then down to 900 RPM just to see what would happen. One thing was pretty apparent right up front, the ECU started to pull timing out in an attempt to pull the idle RPM down. The idle RPM did pull down just a tad, but not much at all different. From here on out, I'll be keeping the idle RPM at 975 based on the cam size I have in this engine and the research I did this earlier.

I'm looking forward to getting my tires mounted and balanced so I can drop the GTM on the ground and turn it around in the garage and do more tuning. I also picked up my steel wheel plug this afternoon and its perfect for mounting my magnetic caster camber gauge.

Shoeless

03-20-2021, 04:50 PM

Got the tires mounted and balanced this last week and it was time to drop the GTM on the ground for the first time. I checked all the clearances through the suspension travel and noted I'll have to install the turn buckles for the front sway bar from the back instead of the front on the control arm. I should have enough clearance for the Stance Air Cups I'll be installing once I get that in. I was actually able to move it under its own power for the first time :cool: Hitting all these milestones here lately are amazing.

https://i.imgur.com/jHBAUhy.jpg

https://i.imgur.com/Bi0M3Fk.jpg

https://i.imgur.com/cLnQb9i.jpg

https://i.imgur.com/ndRgkS5.jpg

https://i.imgur.com/tisFola.jpg

https://i.imgur.com/mZM8yez.jpg

dlud

03-21-2021, 12:06 PM

Congrats! What radiator are you using?

Shoeless

03-21-2021, 06:37 PM

Congrats! What radiator are you using?

Thank you Sir!! I’m using a Dewitts C5 radiator and I also pick up their fan shroud.

beeman

03-21-2021, 08:18 PM

Great to see you making big progress!

Shoeless

03-23-2021, 06:30 AM

Great to see you making big progress!

Thank you Sir!!!!

I've got some video of driving around the block to look through and a bunch of logged idle data I have been pouring over to see what to change next LOL. I should have logged some of my driving as I had an error in the DBW pedal, oh well another great excuse to cruise around the neighborhood :cool:

Shoeless

03-28-2021, 07:28 AM

Had a fairly busy day yesterday throwing the body back on for the first time in years to start working fitment of the rear firewalls and seats. The body seemed to go on fairly smooth enough with the forward and aft locations being held by the door striker plate and forward frame rails and of course had my hands full adjusting the rear of the body to the frame. After a ton of back and forth, I've got the left and right within about a 1/16 of an inch, what a PITA, but I have a question about the height.

The manual says to align the bottom edge of the licensee plate recess to the top edge of the trans mount. Well, the bottom edge of the license plate recess isn't flat or parallel to the ground. Looking at pic 2 and 3 below, what point should be aligned to the top edge of the trans mount?

Looking at pic 4 from the underside, if I lay a straight edge on top of the trans mount, and slide it rear until is just starts to touch the body, my height is set closer to the location I point to in Pic 2. I believe I have this too high at the moment as the flat where the license plate would go is not perpendicular to the ground, its actually angled forward quite a bit. Because of this I had to bend the FF aluminum bracket. I think this is because I have the body too high.

Pic1
https://i.imgur.com/WLAQVYF.jpeg

Pic 2
https://i.imgur.com/9KywpIt.jpeg

Pic 3
https://i.imgur.com/PiU4dli.jpeg

Pic 4
https://i.imgur.com/EYoH8wM.jpeg

VRaptor SpeedWorks, LLC

03-29-2021, 08:26 AM

Shoeless

03-29-2021, 09:21 AM

Pic 2 is what you want aligned with the top corner of the chassis. You are correct in the fact that the license plate area is not vertical.....so a 90 degree bracket does not work. We always make our own bracket here from 14ga steel that covers most of the license plate area and bend it to an angle that matches the body. We attach the bracket to the license plate area and just let the bottom edge sit on the chassis while we move the body around on the chassis to get it aligned. Once we get the body aligned, we get in there with a 90 degree drill and pop a couple 1/8" holes thru the bracket into the chassis and cleco it in place. If you try to align the bracket to be square with with the back edge of the chassis instead of letting the bracket be where the body wants it to be...you end up with what you have going on there where it looks like the driver's side bolt is warping the body inboard.

Thanks for the reply Shane, I had a feeling I have this too high at the moment and will need to redo this step. Quite the PITA. I'll have to drop the exhaust down a bit before I reset this height, but I knew I would have to do this. Plus once I get the body centered I can center the exhaust as well. Then onto centering the wing mounts based off the exhaust location once I take the body back off.

Good catch on the drivers side bolt warping the body. Its was very minor out on the car, but once I took a pic with a flash and posted it here, it stuck out like a sore thumb and I immediately went out and loosened that bolt up. I'm a total newbie when it comes to working with fiberglass.

When I'm centering the body, is it more of a "flexing" of the rear part of the body or is there a sweet spot alignment wise where it will fall right in place? If I let the body rest on the rear without any force it's obviously more towards the driver's side. Seems like I need to get the left and right alignment held in place with a bracket with slots and then force the body to a level state.

VRaptor SpeedWorks, LLC

03-29-2021, 10:21 AM

I guess first off, you should have the passenger side of the body pulled up tight against the chassis tube at the front of the passenger door opening. That normally leaves about a 3/8" gap between the body and door striker bracket. We cut the door striker off the chassis, clamp it to the body and re-weld/tack it in place (then full-weld it once the body comes back off for paint). Doing this, instead of keeping the body tight to the striker, pulls the body toward the passenger side closer to where it needs to be.

We do both the centering and leveling based off the wheel arches. Measure from the coil-over mount out to the wheel arch to center it up and then with the suspension at full droop, measure from the hub up to the wheel arch on both sides to "level" it. We also use a level on the back of the body to verify that leveling the wheel arches to the suspension does not throw the rear of the body way out of whack.....and if so, we fudge things to an acceptable level....usually biased on getting the rear of the body level with the chassis. We do all of this with the body vice-gripped/clamped to the bracket and the bracket vice-gripped/clamped to the chassis. For side to side adjustments, we just loosen up the clamps to the chassis and let the bracket slide back and forth on the chassis tube. If we need to adjust the level, we loosen up the clamps to the body and twist the body and necessary to get it level. Once we have it where we want it, then we drill thru the body/bracket and cleco that and then drill thru the bracket/chassis tube and cleco that.

beeman

03-29-2021, 09:55 PM

Shoeless

03-30-2021, 08:20 AM

Got a welder yet Sean? :p
My rear bodywork is basically unchanged. I also welded up a support bracket to support the rearmost body at the back of the transmission subframe. I also cut the very rear off the subframe and rewelded to match the sorted out body position.
I'll add: I built my Cobra before I knew how to weld. I had multiple compromises because of it. ie bolting on components that should have been welded on, accepting things how they came from FFR, etc. Learning to weld was a very quick process, and opens up countless opportunities to the point that I would say learn to weld first, then build a car like this. Yes, it can be built as delivered but you WILL be compromising. You can do everything that Shane and I are recommending in these past 2 posts with a $100 Harbor Freight flux wire welder and the painted result will look excellent. Ideally you would want a MIG setup, but you are looking at $750+ after getting a gas bottle, and for little stuff like what you are trying to fix here, you don't need that. These are non-critical welds, I wouldn't go near the safety cage until you really know what you are doing.

These are great points and I wish I would have picked up welding before I started the build. I would have easily been able to address a number of items. One of the sister companies to the one that I learned all the wiring from has kicked off a motorsports fabrication company with the same format of teaching. I ended up buying a VIP account so I have access to every class they currently offer and will offer in the future. With that, I'm going through their TIG welding class right now and really enjoying the content. Shane actually recommended to take a look at the TIG machine linked below at HF and so far I'm pretty impressed with the feedback it has. Plus one of my neighbor's kid is in a vocational path at school for welding and gave me some great feedback on this machine as well. I wish I would have done this earlier, but I'm seeing more and more things that will require cutting and welding to fix.

https://www.harborfreight.com/protig-205-industrial-welder-with-120240-volt-input-56254.html?_br_psugg_q=vulcan+tig+welder

beeman

03-30-2021, 09:26 AM

crash

03-30-2021, 11:16 AM

It's like anything else once you have the proper tool. You don't even think about it, you just solve the problem. Then, after awhile you find yourself looking back and wondering how you functioned without that tool.

"A grinder and paint makes me the welder I ain't!" LOL

Those tanks look really good. Especially if this is one of your first aluminum projects.

Shoeless

03-30-2021, 11:38 AM

I actually just got a TIG machine and love it, the ability to weld aluminum and stainless opens even more options.
I got a Lotus Esprit Turbo, and the surge tank was on its last leg, corroded inside and out. I wanted to fab up my own out of aluminum, it's a dual tank system for engine cooling and chargecooler circuit. I got the TIG unit and played with it for a few hours, then went to town on the surge tanks. Not perfect, but I was impressed with what it could do with minimal practice. Will be a while before I'm stacking dimes (I didn't do those perfect tank welds, just some of the bungs and combining them into one unit).

I got this Primeweld unit based on reviews, especially customer service, and it has been great so far and can do 110/220. And I really like the TIG videos that WeldMetalsOnline has on Youtube, they recommended that unit.
https://weldmetalsonline.com/collections/welding-machines/products/primeweld-tig225x-ac-dc-tig-welder

I came across that welder as well. Glad to get some good feedback on it. I've also got to get my electrician over to run me a 220 plug for welding and I mine as well put a 220 in for my wife's electric car charging. She just picked up a Chevy Bolt fully electric and it get about 250 miles per charge. I does ok on 110, but if totally drained it takes about 1.5 days to fully charge. Funny that I'm over here building the GTM with crazy V8 power and she has the all electric car. She has halfway convinced me to build her an all electric something next, so picking up welding and other fabrications skills will darn be mandatory.

@Shane:
1. After you get the body in a good spot and cleckoed in place, do you go back and bolt everything or just rivet it?

2. For the door striker on the passenger side. Do you cut the whole thing off the bottom square tube and also at the round vertical tube and then just slide it down the square tube until it butts up against the body? I image I'll have to add a piece to this bracket to be able to take up the gap I create between the vertical round tube and this striker bracket.
I appreciate you answering all my questions on this.

VRaptor SpeedWorks, LLC

03-30-2021, 05:10 PM

1. Normally, we just put about four 3/16" rivets thru the license plate area into the bracket in a square pattern (I cut the bracket tall so it covers most of the license plate area) and then 3 or so rivets thru the bracket into the chassis tube. That doesn't happen until the body is painted and final-installed. While we're working on the car, we just leave it cleco'd with 3/16" clecos once we get the body centered and leveled. PS....don't drill your rivet holes where your license plate holes are going to need to be!

2. We use a 4.5" angle grinder with cut-off wheel to cut the striker off flush with the top of the square tube as far as we can (basically just cutting thru the weld) and then use a sawzall to finish the cut since the grinder wheel will not go deep enough.....and we normally end up doing this with the body on because I always forget to do it until the body is already on and I always kind of hope that it won't need to be done....but it always does. We just cut it off right behind the striker itself where the narrow part of the rearward support is....we don't cut that whole support bracket off.....and then, yes, we cut a 5/16" or so wide chunk of steel to fill that gap between the striker and the support. Once it's cut off, we just use a spring clamp to clamp the striker to the body and then shift it around until the bottom lines up with the chassis where we want it and get a few really good tacks welded and the 5/16" chunk welded in so it can't bend or go anywhere. Once the body comes off for paint, then we full-weld the striker back to the tube and weld the back side of the gap-filler.

Shoeless

03-31-2021, 05:12 PM

Shoeless

04-03-2021, 09:53 AM

Following Shane's advice above on positioning the rear body, I started out by taking a section of thin sheetmetal and bending it to the angle needed between the trans bracket and the rear face of the body and then transferring that to a larger gauge aluminum piece I had left over that I didn't use from the InfinityBox mounting plates I picked up. From there I set the aluminum bracket in place and noticed a substantial rocking motion left to right caused by excessive glass right in the center of the back side of the license plate location. From my first attempt at bolting a bracket in place, this was the reason the fiberglass was flexing once I bolted it down. So I broke out the angle grinder and went to town on removing the peak of material in the center of the back side of the license plate area. Once that was knocked down, I hit it by hand with some 80 grit just to smooth any further imperfections out. The aluminum plate now rests perfectly flat against the trans mount and the rear side of the body.

https://i.imgur.com/YTagOpR.jpg

https://i.imgur.com/gAn0DZo.jpg

https://i.imgur.com/uTCknUK.jpg

Next, I moved on to leveling the body. I needed to cut out a bit more of the exhaust cutout area to get to a nice reference location left and right in addition to measuring from the wheel arches down to the center of the fully drooped wheel hub. I took some pieces of wood and wooden shims and balanced them on top of the wing mount I have installed on the rear trans mount and this worked out perfectly to make very minor adjustments until I was completely happy with a level body. Checking with a straight edge sitting on the trans mount to the cutout opening is darn near perfect left and right and measuring from the wheel arches down to the hub is within a 1/16". I'm going to count this good enough and looks rather nice when I stand back and view the full rear end. I've got some longer clamps on order that were supposed to be here yesterday, but got delayed before I drill a cleko the license plate location and then move on to the left and right positioning.

https://i.imgur.com/tuMGWab.jpg

https://i.imgur.com/Ba6AECp.jpg

https://i.imgur.com/Lvn2bJL.jpg

VRaptor SpeedWorks, LLC

04-05-2021, 08:41 AM

Sounds like it all worked out well! The bracket you made looks like it's almost identical to what I make here. One thing on fiberglass....you don't ever want to leave a sharp corner anywhere. Where you have the bottom corner of that license plate area cut square to the body.......if you look at the 4th photo down in your last post, the corner where the scale is, the corner is cut square and just above the scale is a tiny little saw cut. You're going to want to take a round file and round those corners out and get rid of that little saw cut to avoid having a crack start there and propagate out from there. Fiberglass is pretty picky that way. Always radius out all of your corners and try not to have any saw cuts like that left in the body anywhere. The bigger the radius you can get away with the better, but on the license plate area like that, we usually just use a 1/4" round file to finish out all of the corners.

A lot of the first GTM's built, we found out that over time, the body will crack out from the 2 top corners of the hatch opening for the same reason.....even with a large radius there, it is still a "corner" and stress point on the body.....so we cut some 14ga steel plates that match the profile of that corner and bond those plates to the bottom of the drip rail with panelbonding adhesive to reinforce the corner to prevent it from flexing and beginning a crack there.

Shoeless

04-06-2021, 04:50 PM

Hey Shane,

Thanks for the pointers on the fiberglass work. Before I started more work yesterday, I took a file out and got rid of those sharp corners. I'll have to keep in mind your pointer on the top corners of the hatch.

I spent a good bit of time yesterday going back and fourth with setting, measuring, adjusting and repeating until I landed on what I thought was a close as I could get for all the measurements (shock tower out to body edge and height from wheel arch to wheel hub). Once I would get one measurement within about 1/16" the other would be out by over 3/8". I finally landed in the left and right to within a bit less than 1/4" and same height wise, about a 1/4" difference. I simply wasn't able to get any closer and hope this is good enough. Comparing the rear body openings around the exhaust to the trans mount its a bit off, but again tried to get everything as close as possible without negatively effecting another measurement.

I then moved on with shifting the location of the exhaust and installing the rear wall in the cockpit. I've still got to finish the full cutouts around the exhaust but the exhaust tips are centered in the body opening. The rear wall also looked really good with gaps all the way around looking pretty close, a bit closer on the passenger side, but overall I think I'm happy. I cut a piece of the bulb seal and tried it all around and I think I have this wall located nicely. So maybe my alignment of the rear body is good enough. BTW how are you guys closing up that little gap between the rear wall cutouts and the role bar? Maybe some neoprene sheet sealant?

https://i.imgur.com/z7gSORh.jpg

https://i.imgur.com/9HIjBTy.jpg

https://i.imgur.com/3klg506.jpg

https://i.imgur.com/V0AxBMc.jpg

VRaptor SpeedWorks, LLC

04-06-2021, 05:17 PM

When we cut the bulb seal for the aluminum window panel, we leave long "tails" of the round bulb seal that will overhang the halo. Once we upholster and install the panel for the final time (before we put the painted body back on the chassis) we take superglue and glue the tail ends together so that the bulb seal is continuous all the way across the roof and down the sides. We have some really "squishy" foam rubber (bought from a lumberyard meant to seal up the rake of a pole building where the vertical steel and roof steel come together) that is about 2"x2", but takes next to no pressure to squish the 2" down to 1/4" thickness. We put a short strip of that on the engine bay side where the halo tubes meet the main "roll cage" tube above the front of the engine in order to help seal that area of the window panel. On the inside, we bevel/fit the hard foam roll bar pads to fit tight to the window panel and then when we wrap the halo in headliner, we but the headliner up against the window panel....so between all of that, it gets sealed up pretty tight.

Shoeless

04-08-2021, 06:25 PM

Shoeless

04-17-2021, 09:49 AM

Not so much of an update other than sharing in typical GTM fashion, I was not happy with where I ended on the rear body alignment, and wondered if I could do better. I thought I had things pretty close, but when something keeps me up at night, I know I could do better. I knocked off work early yesterday and redid the rear body alignment.

I put the GTM back on the jack stands and shimmed it as close as possible with my large level and my laser level as I could get it left and right. From there I shimmed the body up once again and re-drilled the bracket one hole at a time checking my alignment up and down. After two holes were drilled through the license plate area, I started to bump the body towards the passenger side with a clamps holding it in place. After a little finesse my left and right was within 1/16" and height to wheel arches from the wheels is under 1/16" from side to side. I drilled the remaining holes double checking all my measurements along the way and I am WAY happier with the fitment now. From there I needed to readjust the exhaust tips to center them in the cut out areas and am very happy it was only a minor adjustment needed there.

Time to jump back to the interior area. I really want to get my harness bar, harness, and seats installed to make this thing somewhat safe and get into road tuning. Supposedly I can actually register it here in FL in this state, so once I get the seats installed I'll do that. Reading over some past posts and directions that Shane provided for locating the seats, it looks like I need to get the doors installed. I didn't think I would be jumping in on the doors this soon, but I guess its time to jump in head first. More notes from Shane on his first step of the doors is cutting the door frame. I've got some more research to do, plus I'm waiting for my welder to come in that I ordered. I decided to go with the Primeweld TIG225 that beeman recommended, but its on backorder until mid May. I'll work around this for now and get some odds and ends done.

Shoeless

04-18-2021, 05:51 PM

Did some work on the interior yesterday. First up was fitting and mocking up the harness bar that Shane was nice enough to build for me. Pretty slick little design I will say. Bolts right in place instead of the shoulder strap for the seat belts. I need to get a couple longer bolts, but this thing fits perfectly. Now I need to really think about the color to powder coat it. I've done several brackets and my wildwood master cylinders in Silver Hammertone and I think I will carry this into the interior. For whatever reason this color seems to hold up a bit better to scratches and dings, compared to gloss black, so I think I'll stick with this color theme in the interior as well. It will also compliment the grey 5 point harnesses I found on Summit. Just need to order those up as well.

https://i.imgur.com/2buCZ2x.jpg

https://i.imgur.com/1wKGd9v.jpg

From here it was time to fit in the fuel tank covers. Per the manual and I think I have seen Shane mention it here that they need to be notched a bit to clear the door striker bracket. It wasn't much, but made some clearance on both covers and then set them in place. I think on the top where it will secure to the rear wall fits nice, same with the bottom into the floor frame. They seem to fit pretty well to the aluminum tunnel aluminum piece that's in the pic with the clecko holding it in place, but a bit of a gap to the next tunnel aluminum piece to the rear of that. From here the manual was a bit confusing on what gets installed first the tank covers or the engine cover. It seems to read that the tank cover would go first, but that didn't look right, so I put the tank covers on first and then rested the engine cover on top. Pretty decent fit on the tunnel aluminum, a bit of a gap between it and the last rear tunnel aluminum piece and then a large gap at the top where it would secure to the rear wall.

Can someone confirm what goes first, the tank covers or the engine cover?

https://i.imgur.com/CAU0C5i.jpg

VRaptor SpeedWorks, LLC

04-19-2021, 08:28 AM

The waterfall (engine cover) goes behind the tank covers. I usually get the tank covers all fitted and installed, then mark the inside and top edges of the tank covers onto the rear window panel with a sharpie. Pull the covers back out and then put the waterfall in place and get it to where it seems to fit the best with the top flange sitting level on the window panel. Once you get that positioned, transfer the tank cover marks to the top flange of the waterfall and mark the waterfall where the bottom edge of the window panel is. You will need to cut those corners off of the waterfall so that the tank covers and waterfall all sit flat against the window panel. When you trim the waterfall, be sure to allow a little bit of extra room for the upholstery....once you get the tank covers upholstered and the vinyl or leather wrapped back around the edge of the waterfall, that adds thickness you will have to account for. I usually extend the cuts down just a bit from where the waterfall hit the bottom edge of the window panel....maybe 1/2" or so. Of course, you will need to peel back the vinyl on the waterfall before you cut the corners back. You can peel it back a bit before you put it in place and make your marks, or mask it off, make your marks on the masking tape and then measure for how much you need to trim...then peel back and trim and re-cover the corners with the vinyl.

beeman

04-19-2021, 09:17 AM

Interesting... I didn't do it that way (yet). So will everything fit flush across the back once it's trimmed? Or do you still have a step off at the transitions from the aluminum firewall to the waterfall?

VRaptor SpeedWorks, LLC

04-19-2021, 01:10 PM

All of the top flanges of the tank covers and waterfall where it bolts to the window panel sits pretty flush. The top edge of the waterfall is never quite exactly the same height as the tank covers, but as long as you get everything so it sits level on the window panel, it looks good. If you try to put the waterfall in front of the tank covers, it just doesn't fit well anywhere...it doesn't want to sit down on the window panel and won't fit right to the chassis....and you will have huge gaps at the transition where the tank covers, waterfall and chassis meet that will be open to the engine bay.

beeman

04-19-2021, 02:00 PM

Shane- so are you cutting the waterfall in the region of this yellow line to make it sit flush with the aluminum firewall? I just assumed you install it like Sean has in his picture. Surely FFR wouldn't have fully contact cemented the vinyl around the back of the waterfall?

146548

Shoeless

04-19-2021, 04:01 PM

Thanks for posting up the edited pic with proposed yellow cut line Dave, that was going to be my exact next clarification question :cool:

VRaptor SpeedWorks, LLC

04-20-2021, 08:14 AM

146592

No..you don't want to cut that whole edge off. That edge is what keeps the waterfall trapped behind the tank covers and "seals" that edge off from the engine bay. I only trim the top corner where the waterfall contacts the window panel and extend the cut down about 1/2" or so below the edge of the window panel so that the edge can "transition" from being flush with the tank covers to being behind the tank covers. That area in red buts up against the edge of the tank cover while the rest of that flange below rests against the back side of the tank cover.

VRaptor SpeedWorks, LLC

04-20-2021, 08:24 AM

146593

146594

VRaptor SpeedWorks, LLC

04-20-2021, 08:36 AM

146595

Shoeless

04-20-2021, 10:58 AM

Awesome Shane, thanks for the clarification and the photos!! Time to do a little trim and see if I can get this to fit up like you are showing.

Shoeless

05-05-2021, 02:26 PM

Hey guys,

I got an opportunity to work on the interior a bit this last weekend. I took Shane's pointer of trimming the top corners of the waterfall to allow it to fall behind the fuel tank covers. I also ended up needing to trim a bit of the bottom portion where it hits the tanks as well. Once I did that, the whole rear wall, waterfall, and fuel tank covers landed in place. I carefully clamped, measured, drilled, and installed hardware and in the end, I think this came out excellent. Once the fuel tank covers are upholstered this should seal up PERFECTLY.

https://i.imgur.com/rlzob5v.jpg

https://i.imgur.com/RComCLQ.jpg

https://i.imgur.com/yU0Kmui.jpg

https://i.imgur.com/GN9cGOo.jpg

https://i.imgur.com/IfO8BUr.jpg

VRaptor SpeedWorks, LLC

05-06-2021, 08:06 AM

Those look great!!

Shoeless

05-23-2021, 10:30 AM

Been playing with my new toy here lately. I ended up getting the PrimeWeld 225x TIG machine a few weeks back and am really enjoying teaching myself how to TIG weld. I started with some simple beads and then tried to start mimicking the joints that I'll be welding on the GTM first (passenger door striker and door frames). I need to pick up some different square tubing and larger filler wire to really mimic the door frame welds, but I'm making progress. Tons of screw ups along the way, but the best way to learn is just jump right in.

https://i.imgur.com/QkL0L8O.jpeg

https://i.imgur.com/fY1NOun.jpeg

https://i.imgur.com/a94GRkG.jpeg

https://i.imgur.com/BMtoP99.jpeg

https://i.imgur.com/HuC7Wbg.jpeg

Shoeless

05-23-2021, 01:42 PM

Time to start roughing the doors in.

Shane,

I found some of your notes from prior posts on where you mention to cut the door frames in half. Before I go and screw this up, is this where you cut both square tubes in half?

https://i.imgur.com/mSzlOCH.jpeg

Shoeless

05-30-2021, 06:57 PM

OK so I have spent the last couple days working on the passenger door and either I am completely inept at this task or its just this much of a PITA for everyone. So I figure before I really screw something up, I better stop, take some pics, and ask some questions. First up was finding an answer to the last post. I keep in touch with a couple GTM owners and it just so happened that one of them had Shane do a lot of work on his GTM and he currently has his torn apart for some updates/fixes. I asked for a pic of the front frame of his doors and I see exactly how Shane cuts them and welds them up with extra square tube pieces. Here is that pic.

Pic 1
https://i.imgur.com/0H4tL4I.jpg

From here, I followed the instructions for how to locate and drill the holes on the front of the door for where the frame attaches to the door. At least I think I got it in the right place, I'll ask a series of questions after I post up my progress and other pics. From here I cut the openings for the hinge and door stop. The hinge pins are offset to one side and I originally put the offset to the inside. After plenty of frustration, I found a post from Shane noting the offset should be towards the outside. So I cut my openings larger to flip this part around.

Pic 2
https://i.imgur.com/lZGRCFF.jpg

I trimmed the body side for the clearance when the door opens per the manual and then tried to mount the door with the hinge pins on the car. This did not go so well LOL. Either I have the mounting holes in the wrong spot or there is a lot of clearance on the door edges that needs to be made to fit in the opening. I started to clearance the front top side of the door as it seems the front of the door needs to go up in the front. I shaved a bit back on the edge where the black sharpie is, but then stopped before I went too far.

Pic 3
https://i.imgur.com/ylmgRAH.jpg

At this point before I did more damage that I might have to repair later, I took the hinge out of the door and set the door in the car and looked at the inside gaps and they seem way off. There is a rather large gap at the back of the door and a very small gap at the front. This would lend me to believe I need to trim back the back edge of the door to physically move the door rearward in the opening. I also looked in the wheel well to see where my cut outs are in relation to the hinge pins and it looks way off. So either I have the cutouts in the wrong locations or the door needs to be raised in the front.

Pic 4
https://i.imgur.com/E9JUMyU.jpg

Pic 5
https://i.imgur.com/sO1VzRn.jpg

Pic 6
https://i.imgur.com/A0dQpzc.jpg

Pic 7
https://i.imgur.com/dRBJj6L.jpg

Questions:
1. Pic 2: Does the location of the holes on the front of the door in pic 1 look correct? I measured 1/2 inch from the bottom corner like the manual says, but the door just doesn't seem to fit in the opening. This could be entirely possible, but I wanted to confirm at least I have these in the right location.

2. Pics 3 - 7: If I have the holes that locate the door frame in the right place, and if my assumptions are correct that I need to move the door rearward and the front of the door up, how much do you guys normally see that has to get removed around the perimeter of the door to get it to fit in the opening properly? It looks like I need to remove about 1/4" off the rear edge and B-Piler to move the door back, and not sure how much I need to remove off the front top (pic 3 area).

VRaptor SpeedWorks, LLC

06-01-2021, 10:41 AM

Sorry...I've been tied up for the past several days trying to get a GTM finished here......just saw these posts this morning. I guess I'll just start at what I see would be the best place......

In Pic 6 and Pic 7, it looks like you need to get the main body pulled forward to be up tight against the frame tube that the hinges are welded to and also inboard to close up that big gap you see in Pic7. Make sure you have the wiper close-out box in place under the cowl of the main body, pull the bottom of the body inboard (below the door hinges) tight to that frame tube at the bottom and let the top part settle where it wants to. Measure from the large aluminum panels that are behind the front suspension out to the wheel arch of the main body to get the cowl of the main body centered on the chassis. If you try to pull the body tight to the chassis at the top part of that tube, it puts the body in a bind, so I usually just let that settle where it wants to be....as long as the wiper close-out box in in place under the cowl. Once you get the main body centered, drill and rivet the body to that tube that the hinges are welded to.

Looks like you have your hinge holes cut so that they line up with the hinges on the chassis. The door hinges need to sit on top of the chassis hinges, so you will need to move those up. I don't cut any holes in the door or mount anything to the door until I get the door fitted to the body like I want it to be. So once you're sure that you have the main body where it needs to be, I just keep test fitting the door to the body and grinding away whatever needs to be removed to get the door where I want it. Yes, in pic6, it looks like the front of the inner door is almost up against the body.......I normally have enough room there to put some 5/8" weatherstripping in there
....so....as long as you can move the door back without opening up a huge door gap on the outside of the door, I would start grinding material off the rear edge of the door to move the door back in the door opening. I try to keep the door so it fits exactly in the opening with zero door gap.....just keep test fitting the door to the body and grinding away the areas of contact until the door fits exactly how I want it to fit on the finished car. For the leading top edge of the door (pic3) where it meets the body, yes you will have to keep grinding away at the door until you can get it raised up AND moved inboard far enough so that when you open the door, that leading point will rotate behind the main body. Again, you want to just keep test fitting and marking where the door is tight and keep grinding off material until the door will go inboard far enough to make that happen.

Once the door is fitted perfectly to the body....THEN I put the door in place and wedge it/tape it/shim it/clamp it so that it is EXACTLY where I want it to be...as much of the door flush and aligned perfectly with the body as possible to get bodywork to a minimum. THEN I go to the front of the door thru the wheel well and mark where the door hinges need to come thru the door to sit on top of the hinges on the frame. This way, you are not using some arbitrary guesswork measurements to figure out where to cut the holes in the door....you can not un-cut the holes.....with the door perfectly fitted to the body, you can know exactly where the hinges need to come thru to sit perfectly on top of the chassis hinges.....make sure you account for the thickness of the hinge bushings.

This is the point where I cut the large weldment off the front of the door frame. I also weld reinforcement plates to the hinge bosses in the flat hinge plates to strengthen the hinges so they can't bend as easily. Cut the holes in the front of the door shell for the hinge plate to pass thru according to you marks. Now...more fun. If you test fit the 1/2" carriage bolts to the hinge plate, you will find that they don't go all the way tight against the plate.....the radius at the base of the square on the bolt binds up on the slot in the plate and holds the head of the carriage bolt out away from the plate. I take an angle grinder and cut-off wheel to square two sides of the bolt up so that the bolts sit flat against the plate and then use the angle grinder to score a small slot on the face of the threaded end of the bolt so I can tell which way to orient the bolt in the slot so my relief cuts in the bolt line up with the slot in the plate. The other problem with the carriage bolts is that the square of the carriage bolt is too high....it sticks up thru the flat hinge plate too far and engages with the slots in the door frame....and that's a very bad thing. Essentially, this will make it so that you will never keep your door adjustments because when you tighten the nut on the carriage bolt, all you're really doing is jamming the square of the carriage bolt up against the slot of the door frame and the flat hinge plate will be completely loose and your door will always fall out of adjustment on you.....so get the angle grinder back out and grind the top portion of that square on the carriage bolt to be round with the rest of the bolt.

Now you can put your carriage bolts thru the flat hinge plate, put the hinge plate thru the holes in the door and then put the front weldment of the door frame over the carriage bolts and install the washers and nuts. Now you can put your door back in the opening on the car and once again clamp/shim/tape it to fit perfectly in the body and get your hinge pins installed thru the hinges. Now you can position the door frame weldment where it needs to be on the door. Normally you will end up near the bottom of the adjustment slots in the hinge plate. Be sure to leave yourself some vertical adjustment in the slots, but if you move the door frame weldment up to the center of the hinge plate slots, it will be too high and your door speakers will hit the door frame....which they may regardless of what you do, but keeping the weldment positioned lower will help avoid this as much as possible. Since you should already have the door shell positioned perfectly where you want it, you shouldn't need much adjustment anyway. Now that you know where the door frame weldment needs to be, THAT is what will determine where to position the 5/16" carriage bolts and that aluminum trim plate that covers the front of the door behind the hinges. Again, position the holes for the 5/16" carriage bolts thru the weldment so that you have some adjustment in the slot to adjust the door in and out. Side note.....in order to get more/enough in/out adjustment for the front of the door, I normally have to trim the "tabs" off of the door frame weldment that end up hitting the door shell flange that the inner door panel mounts to.

VRaptor SpeedWorks, LLC

06-01-2021, 10:42 AM

You will need to make a clearance cut in the main body for the leading edge of the door to tuck into/behind the body when the door opens. You can figure out how high up you need to go with the clearance cut by sighting down thru the door hinges on the chassis. At the intersection on the body where the hinge holes line up with the edge of the main body....that is how high the clearance cut needs to go. You will need to make that like part of the body like a knife-edge in order to clear the door while the door opens. Do not cut the door gap larger there to make room. Just thin the cut down to a knife edge.

That should take care of the front of the door. You should be able to hang the door, put in your hinge pins and open and close the door shell.

Now for the door latches. No need to cut that huge slot out of the fiberglass for the door striker. You already have the door fitted exactly how you want it, so you have no need for an inch of vertical adjustment. We normally cut the passenger striker plate off of the chassis and move it forward tight to the body and re-weld. Then find the exact center of the slot in the striker plate and drill an 1/8" hole thru the body. Now install your door, install the hinge pins, clamp/shim the rear of the door so it is in exact alignment with the body, reach in thru the window or thru the rear wheel well with a long 1/8" drill bit or sharpened rod and poke thru the 1/8" striker hole in the body...make sure you're holding it square to the striker plate and spin it up against the door shell enough to make a mark in the gel coat. THAT mark is the exact center of the latch with the latch closed. Now you know exactly where the latch needs to be installed. Since you are going to end up cutting your gel coat mark off when you cut the hole for the latch to fit in the door, I normally make an extended "crosshairs" mark before I start cutting so that even after the hole is cut in the door, I can still find the center of my mark with the extended horizontal and vertical marks on the door shell. with the latch hole cut in the door, now you know exactly where the latch mounting plate needs to be attached. Once you have that attached and the latch positioned so it is centered on the crosshairs with the latch closed, you can position your door frame inside the door.

Normally, the angle of the plate that the latch plate attaches to on the frame will not lay flat with the door frame, so we end up cutting that end of the door frame also. Normally we don't cut it all the way off the frame....just weaken it enough so we can bend it to match and lay flat against the latch plate. With the door laying flat on some stands or a table, lay the door frame inside the door and use the inner door panel to determine how high you can shim the door frame up before the door frame hits the inner door panel. The latch side of the door just bolts up to the latch plate, but the front of the door frame you want to shim up as far as you can without interfering with the inner door panel. Once you figure out where that point is, check how the latch end fits and bend the frame accordingly until the door latch plate sits flat against the door frame. Once that's done, you can bolt your latch end together and weld up the frame tubes at the front with some gussets like I did in Pic1.

Shoeless

06-01-2021, 11:34 AM

Hey Shane,

No need to apologies at all for any delays trying to get a car finished up at your shop. The pics of that finished up GTM are absolutely amazing!!!

I really appreciate you taking the time to post up these detailed instructions on how you approach the doors. I'll admit, I was completely lost and things just didn't look right so I thought it best to stop, step away, and reassess the situation. I'll get some good practice in repairing the areas of the doors I've already cut up trying to follow the lovely build manual.

Thanks again for posting this up, I'm sure I'll have some more questions along the way, but now I have at least an idea of what I need to go do for now.

Shoeless

06-02-2021, 05:57 PM

Last couple days I took a couple steps back and reassessed where I'm at. Taking this one step at a time, I need to get the body aligned and pulled forward up against the passenger side square tube in front of the door opening. I took the wiper closeout and front fire wall and set them in place. From the pics it looks like the front portion of my body is too low. I'm able to force the fiberglass up enough for the holes that FF put in the front firewall when they attached it to the body for shipment to me, but not sure if that's really what I should be doing here.

https://i.imgur.com/aQbMsl0.jpg

https://i.imgur.com/pePHoln.jpg

So I started pulling a shoving and trying to move things around and the body just feels bound up. Looking inside the passenger side door as I'm trying to get this pulled forward up against the door square tube and inward and the body is actually hitting the roll bar preventing much of any movement.

https://i.imgur.com/g8D4aUP.jpg

https://i.imgur.com/m1gpHvR.jpg

At this point I stopped again before breaking anything and pushed the body inboard and and took another pic from the front wheel well. And forced it as far forward as I could and took another pic.

https://i.imgur.com/JMhyH2U.jpg

https://i.imgur.com/dC5gQRQ.jpg

This may be looking a bit better, but I still have more of a gap at the top than the bottom when looking in the wheel well and the fiberglass is closer to the frame at the top than the bottom when looking out at the door frame from the interior.

I even tried removing my rear body mount around the license plate area and that didn't make any difference.

I'm stuck once again and unless I file down the body around where it is hitting the role bar to make clearance, I don't see much improving around this area at all. Am I missing something here, or should I start to remove material around where the body is hitting the role bar to see if I can get this to move more in the direction I need it to?

Also, should the body naturally butt up against the square tube or does it need to be clamped (i.e. pulling it forward to meet the square tube) to allow me to rivet it in place?

VRaptor SpeedWorks, LLC

06-03-2021, 08:38 AM

That's all very common stuff that you're running into.

1. First 2 pics.....Ignore where that alum cowl panel placement was from FFR. You need to put bulb seal on your wiper box/close-out and get that under the cowl where it belongs. That will lift the cowl up where it needs to be. As a side note, we usually cut that wiper box in half and slide the two halves together a couple inches and rivet it back together so it's not so long (leave it the same height.....just shorten it length-wise) or you tend to run out of room in the top main alum panel that the wiper box sits on for the AC vent and defrost hoses to come up thru that panel because the wiper box is covering up the area that the hoses need to come up thru.

2. Pic 5 looks a TON better than it did before. We just make sure that the body is tight to the tube at the bottom (like you have it in pic 5) and sort of let the top part do what it wants....which is largely determined once you get the bulb seal on the wiper box and get it positioned under the cowl and the body centered by measuring from the alum right behind your sway bar mounts out to the wheel arch of the body on each side of the car to center the cowl up. Yes, we've had several cars where the halo is positioned too far to the right and prevents the body from moving inboard. Most are acceptable and as long as I think there will be enough room for the roll bar cover and headliner (we install headliner inside the A-pillar of the body), we leave it alone. There have been....I think 3 cars where the halo was so far to the RH side that we could not get the body where it needed to go and had to cut the base of the halo tube loose and move it inboard and re-weld. PITA, but much less so than trying to "work around" the fact that the body can't be centered.

3. Last pic....yes, we clamp that part of the body forward so that it is tight to the rear face of that square chassis tube all the way from the top to the bottom.

Shoeless

06-03-2021, 10:03 AM

Hey Shane,

Well, I'm glad I'm not the only one that runs into issues like this, albeit very frustrating and really testing my patience on this build. Trying to stay as positive as I can, and your feedback is helping me know that it's not me doing something wrong, so I really appreciate that.

I'll go ahead and chop the wiper close out in half, rivet it together taking up 2", get the bulb seal on there, and set it in place to bring the body up (ignoring the holes that FF drilled for the front firewall). From there I'll check my left and right measurements to make sure the body is centered and then see if I can clamp the passenger door vertical fiberglass up against the frame.

Now that you mention you have ran into a few GTMs where this front role bar needs to be cut, pulled inward, and rewelded, I think I may need to do that. When I compare the driver's side to the passenger's side, there is a nice gap between the body and frame on the driver's side, but the passenger's side is horrible with the frame hitting the body in a couple areas. I'll get all the other stuff above done and see where I end up. I also threw the interior pieces in and where the passenger side interior part is supposed to meet the role bar there is a large gap as well, making me think this does need to be cut and brought inboard. Glad I'm teaching myself how to weld :cool:

You wouldn't want to spend an extra week in S FL helping me out on my build would ya?

VRaptor SpeedWorks, LLC

06-03-2021, 05:15 PM

Hey Shane,

You wouldn't want to spend an extra week in S FL helping me out on my build would ya?

I would actually love to do that....but not sure how that would work with the rest of my schedule?

As for the wiper box, I'm not sure how much I normally take out. I usually cut it in half, then position the halves in place under the cowl and figure out where each leg rests on the top of the chassis and figure out where my vent hoses are going to come thru and shorten it accordingly....

Shoeless

06-04-2021, 07:19 AM

I would actually love to do that....but not sure how that would work with the rest of my schedule?

As for the wiper box, I'm not sure how much I normally take out. I usually cut it in half, then position the halves in place under the cowl and figure out where each leg rests on the top of the chassis and figure out where my vent hoses are going to come thru and shorten it accordingly....

Thanks for the pointer on the position of the close out box, that make sense to position it over frame tubes for better support.

If you ever find an opportunity where things may be slow at the shop, let me know and I'd be more than willing to work something out.

Shoeless

06-04-2021, 02:55 PM

So I spent a little time this afternoon fooling around with the body fitment with not much success. The front of the body is bound up against the sheetmetal pieces that go behind the suspension. The driver's side is really scraping up the body and the passenger side is hitting but not as bad as the driver's side. Looks like I'll need to blend the sheet metal back a bit so the body isn't scraping against them when I pull the body off. At the moment its not letting me pull the body up to slide in the wiper close out as it scraping against the sheet metal.

https://i.imgur.com/NGVqRvq.jpg

https://i.imgur.com/5DGxiQj.jpg

From here I decided to put the interior dash pieces in place just to see what it would look like, especially what the passenger's side role bar around the a-pillar would look like. The driver's side seems to fit nicely around the body opening and then butt up against the roll bar nicely. The passenger side, not so much. The cutout in the body is scraping the dash panel and the panel itself is nowhere near close to the role bar. The joys of a GTM.

https://i.imgur.com/df0xI94.jpg

https://i.imgur.com/QyJhgmx.jpg

https://i.imgur.com/xtmcWHi.jpg

https://i.imgur.com/WLTD3Xx.jpg

https://i.imgur.com/teSOMcs.jpg

crash

06-04-2021, 04:20 PM

Let me first start by saying that I am not very experienced at anything to do with a "stock" GTM. I am no expert on fitting GTM bodies to GTM chassis.

What I do have experience in is fitting fiberglass bodies to cars.

Take this with a grain of salt and consider that this advise is probably as valuable as what you paid me for it...

I start with the chassis. This is why I stress that it is very important to be accurate and square from the first tube to the last when building a chassis...because if you are not, it will have far reaching effects down the road.

That said if you have any confidence that your chassis is true and square, then the next step would be to mount and align the suspension, and USE THE WHEELS AND TIRES THAT YOU WILL BE USING WHEN FINISHED. Again, critical because if it is not end state correct things will be off. I consider these things to be so critical because really the only things that the body interacts with that you see from the outside are the wheels. I have said this many times...the wheels are crucial to what the end product vehicle is and they need to be determined and purchased at the START of the build, not the end.

Okay, now assuming you have those elements I position the body based upon the fitment to the wheels. I know there are issues with the GTM bodywork on the front firewall and also in the wheel arches of the hood and I did correct those on my body before starting to align to the wheels. You may find that is too much work and following the manual is easier ,but I know no bounds when it comes to cutting and fitting. Then once the body is as square as I can get it to the wheels/chassis, then I worry about the other stuff. Again, cutting and altering is not something I shy away from.

Now all that said, I would listen to Shane much more than to me as my method, while ending up with a clean, square finished product, may not be practical for a GTM that is anywhere near "stock".

I guess what I am getting at is if nothing is working and you have to start somewhere, I would fall back on the wheel alignment and then work from there. That should at least get you close to a starting point.

Maybe Shane wants to join in and say I'm full of crap for a GTM and that is fine. He is the expert. The above is just what has worked for me for decades of doing body fitment starting from zero...which the GTM obviously does not as it has many points that FFR wants you to "hit" with the body.

Good luck.

dlud

06-04-2021, 07:06 PM

I found that when I put the passenger door on the door hit the passenger side dash pod. I eventually cut out over an inch to get a decent fit. I also had to alter the passenger pod fit around the roll bar. Others have reported the same or similar fit problems with the passenger pod. The driver side fit ok. 149064149065

Shoeless

06-05-2021, 08:21 AM

Crash,

I really appreciate the response above. I'm warming up more and more to the idea that there will be things i'll need to cut and fit around the frame. I'm waiting on my order of stance air cups to come in to drop the GTM back on the ground and get a first crack at setting the ride height and an alignment. At that point I can at least see what the fitment of body to the wheels looks like.

dlud,

Thanks for pointing out that you had to make some adjustments to the passenger pod. I guess I missed this in my searching for items that would need correcting. I'll go spend some time reading up on this. Thank you Sir!!!

VRaptor SpeedWorks, LLC

06-14-2021, 08:22 AM

Dash pod fitment......yes, you will have to trim those to fit the chassis and body and doors/door panels AND WINDSHIELD. I do think that later on in the Gen II kits, FFR shortened up the dash pods so that they don't hit the doors, but I would not count on that. I think on every GTM we've built except maybe one....we ended up having to cut the entire end of each dash pod completely off, move it inboard about 5/8" (as far as you can move it without getting into the dash vent opening profile) and bond it back in place. Yes, this is a major PITA because you have to peel the upholstery back without damaging it and then try to glue it back on after the dash is modified without it all bunching up on you. Use a paint stick or similar to lay up against the body from the A and B pillars forward to simulate the windshield bottom edge and mark and trim the dash pods to clear the windshield.....which will also involve peeling back the upholstery, making your cuts, then gluing the upholstery back in place. Once peeled back, I bridge across the upholstery to the dash with masking tape so that while I'm trimming, chunks of fg/plastic don't get underneath the upholstery....that will show thru on the top side when you glue it back down.

Shoeless

06-21-2021, 09:07 AM

Hey fellas,

First, I'd like to give a huge shout out to our professional builder Shane. He was vacationing in S Florida a little while back and graciously offered to swing by my place to check out my build. It was an awesome opportunity to not only share in person about my build, but also ask all kinds of questions for where I currently am. Shane took the opportunity to answer every single question I had and pointed out areas to help me get the body in place where it should be before moving on to the doors. I can't thank him enough for taking his time out of his vacation to swing by my place.

With that, I made some very nice progress this last week. I had my neighbor and wife signed up for helping me pull the body off, allow me to make clearance, put back on, and repeat until I was happy. I ended up clearancing the sheet metal behind the suspension quite a bit, more on the driver's side versus the passenger, but the gap is now even on both sides and I ended up shaving down the thickness of the fiberglass around the passenger side role bar.

https://i.imgur.com/KBoTrDa.jpeg

https://i.imgur.com/mfioMvm.jpeg

I was also able to really pull up the body to the passenger frame rail. From here I measured left and right to the front wheel well opening and drilled a few holes and riveted the body in place.

https://i.imgur.com/tJ1Ghl8.jpeg

Next up, I cut and riveted the wiper close out box put the bulb seal on and slid under the body. There is a little gap on the drivers side where I may spread this box apart a bit to find a good spot on the body to close this out, or cut a little piece of sheet metal and riveting that in place to help take up the gap.

https://i.imgur.com/SIYoSmd.jpeg

https://i.imgur.com/N3vhAdV.jpeg

I also took the opportunity to throw the wing on there and mark the cutouts. I'll probably measure and check a few more times before I cut the openings as one leg is not perfectly perpendicular to the other. Measure 20 times and cut once ;)

Next up fitting in the doors. I spent a couple hours filing off high spots on the door to get it to fit into the opening with no gap as best I could. Probably need a little more work to tweak it perfect, but I'm now ready to throw the hinge frame in and see where I'm at.

beeman

06-21-2021, 02:25 PM

Great updates.
Shane has always been great to talk to / work with over the phone.

VRaptor SpeedWorks, LLC

06-21-2021, 03:12 PM

Shoeless

06-22-2021, 08:20 AM

Was my pleasure to come up and meet you in person and see what you have going on with your build! That cowl height is looking much better now that you got some clearance at the aluminum panels.

BTW....Sean took me and my family out for dinner afterwards....so I'm not sure that he got the best end of that deal. ;)

My wife and I thoroughly enjoyed taking you and your family out to dinner as a token of our appreciation for you guys taking time out of your vacation to come by.

Shoeless

06-28-2021, 02:17 PM

Well, I got my first real taste of messing with the doors over the last couple of weeks getting them roughed in. After Shane's visit I went back took my time on the passenger door following his instructions above and working towards making the door just fit the opening and being able to swing open and closed. After a handful of days putting in an hour or two here and there, I was finally happy with the passenger door. The body lines on the rear match up really nicely and the front sweeps into the pocket that is cut out on the front. It was noted that this pocket opening should almost be a knife edge in the fiberglass and I now understand why.

https://i.imgur.com/cF6Q5sL.jpeg

https://i.imgur.com/VoJ8j2S.jpeg

After my success on the passenger side door, I got up early on Saturday and knocked out roughing in the driver's side in one long day. Thankfully my new 3M respirator wasn't too bad wearing it all day. You can see in the first pic where I made the original cuts trying to follow the manual. That was a complete mistake, but I guess this is an opportunity to re-glass these areas and make them look nice. I also ended up bumping the square holes up by about 0.25" to move the door frame bracket a bit higher, so now I have rectangular holes behind the sheet metal. Following the same advice of getting the door to barely fit the opening and knowing what to cut and by roughly how much, made the driver's door much easier. I did have to grind down on the body on the bottom side of the door opening as it wasn't straight at all. I first started to remove material from the door, but saw that it was getting out of flat on the door just trying to fit in the opening. I'll probably have to add some glass on the back side just to make sure this area is reinforced enough. I also noted that the b-pillar on the driver's door will definitely need to be cut on the back side and pushed towards the body as it sticks out too far, the passenger's side wasn't like this for me.

https://i.imgur.com/C7A2GSS.jpeg

https://i.imgur.com/MvxZRYF.jpeg

https://i.imgur.com/AkQN4fm.jpeg

Overall, I'm pretty happy at the moment. I ordered a larger mandrel from my riv-nut tool to use for the seat brackets, but it won't be in for a week or so. So I guess I can work on getting the seat tracks on the seats themselves and maybe put the strikers and frames in the doors while I wait for my tool.

VRaptor SpeedWorks, LLC

06-29-2021, 08:20 AM

Shoeless

06-29-2021, 09:08 AM

Here's another thing I forgot. You may have noticed that you can't open your doors very far before they bind up on the chassis hinge points. We always cut those back to allow the door to open as far as possible.

150037

150038

Awesome, thanks for this pointer Shane!!! I did notice the doors would bind up on these brackets and not open up as far as I thought they should. Now I know the fix :cool:, thanks again!!!

beeman

06-29-2021, 10:36 AM

Shane, we need to get these newbies comfortable with their Sawzalls and grinders! :p

Shoeless

06-29-2021, 12:31 PM

Shane, we need to get these newbies comfortable with their Sawzalls and grinders! :p

HAHAHA, I'm slowly getting there :cool: especially now that I'm getting some TIG welding practice under my belt.

VRaptor SpeedWorks, LLC

06-30-2021, 08:29 AM

Shane, we need to get these newbies comfortable with their Sawzalls and grinders! :p

HAHAHA, I'm slowly getting there :cool: especially now that I'm getting some TIG welding practice under my belt.

Yup!!....anything you can cut and grind, you can also weld back together now!

Shoeless

07-11-2021, 08:56 AM

Hey guys,

Hope everyone got to enjoy some time off for the 4th of July holiday weekend. I was gifted with an extra day off as the last furlough day over the last 6 months at work so I got to spend some extra time on the GTM. The task for last weekend and this weekend was to get the seat installed. I picked up Shane's seat brackets to use in conjunction with a set of sliders for both the driver and passenger side. The driver's side took me quite a bit of time bouncing back and forth between the direction and seeing where the seat would actually sit in the car. I can now totally understand why Shane shared that its best to do this with the doors on an in place. A slight adjustment on the location of the seat would cause it to interfere with the door. After some adjusting I got the driver's side in a perfect location. After bolting everything down I checked the slider and everything works perfectly. The passenger side is a lot tighter fit than the driver's side, but went much faster than the driver's side since I had the general idea of what to do.

https://i.imgur.com/9Bbmnzh.jpeg

https://i.imgur.com/OpZumar.jpeg

https://i.imgur.com/MQAD6A7.jpeg

https://i.imgur.com/iX6oC2Q.jpeg

https://i.imgur.com/qRnuNoP.jpeg

https://i.imgur.com/iCzbvZ8.jpeg

VRaptor SpeedWorks, LLC

07-12-2021, 08:14 AM

Shoeless

07-12-2021, 02:27 PM

You should have experienced the original GTM seats! Those were twice as fun. We have lots of GTM's come in where the owner has already mounted the seats, but does not have the doors on the car yet....and the door won't close once you try to install them.

Nice work!

Thanks again for the detailed instructions you sent with the brackets!! I followed them step by step and landed everything as perfect as I could location wise. I'm very happy with how they turned out.

Albeit the quality of the seat coverings is not so great and the piece of fabric that was glued to the fiberglass bucket that the Velcro sticks to totally fell apart. No worries, these and the majority of the interior will be professionally redone by someone with a lot more experience than me. I figure if I can rough everything in and then hand it off to someone to stitch and cover for me, I'll be very happy. I'm thinking of black leather with green accent stitching, and diamond stitching on certain accent pieces like the rear wall and the center inlay of the seats should compliment itself nicely. I've seen some nice over the top GTM interiors and I must say I'm impressed.

Shoeless

07-15-2021, 07:39 PM

Hey guys,

Just over three months ago, my Braille B3121 battery stopped holding a charge and I sent it in to Braille for warranty consideration. I was told there were some delays due to covid, but hopefully it wouldn't take too long to get in the components they needed to build up a replacement. Every couple of weeks I would check in with Braille via email and would always get a reply within an hour or two from Tori letting me know that unfortunately there were no updates. After a couple months of this she offered up if another of their AGM offerings would work for me. Unfortunately that wouldn't work, but I started to look at there lithium offerings.

I looked at one model in their Green-Lite Lithium line and fired off several technical questions, and even some follow up questions on the B3121. I received a response from Braille's tech department that the model I was looking at wasn't designed for high displacement engines, and that even the load my LS3 would place on a B3121, would cause its life to be cut in half. The tech support guy recommended for an application like ours, an i34RX lithium would be perfect. He also threw in there if I wanted to stay with a battery the size of the B3121, I would have to step up to the ML30C. This is their most powerful lithium battery available and has been used by the Corvette Racing team for 11 years, Ford with their GT program for 4 years, the Lexus RC-F GT3 program, and many more. Braille was even running some specials for a lithium specific charger as a package selling with the ML30C.

Well, after thinking this over a bit, I jumped in and said let's do it. Tori applied the full warranty cost of my B3121 against my new order and put the order in. This was on Tuesday, and today, my package arrived. I did not expect such a timely order, but boy was i happy. I knocked off work early, installed the battery, and fired the GTM up. Holy crap, it was literally a bump of the key and she came to life. Braille claims a full volt higher than lead cell and less voltage drop while cranking. Not to mention several other benefits over the old antiquated lead cell batteries. This thing is literally a work of art encased in its very own carbon fiber case.

Since I am running the newer CTS-V alternator, I also checked in with Braille for the proper charging voltage as I can change that via a PWM signal from my standalone ECU. This battery is also standard charging system friendly and works great with anything from 14.0 to 14.8 Volts. So I plugged in the laptop to see what voltage was being put out, and was a little stumped that it was only outputting 13.6V. I tried changing the duty cycle in the software and there was no change in voltage output. After some research, I discovered I have the alternator hooked up incorrectly and the alternator will default to 13.6V if its not set up correctly. So I either have it hooked up incorrectly or my PWM signal from my ECU is incorrect. I'll have to pull out the bench o-scope to test the output from the ECU and correct the incorrect wiring that I know I have. Hopefully this will solve my charging voltage issue, and I'll stick a fork in this and be done :cool:

https://i.imgur.com/UCURE1g.jpeg

https://i.imgur.com/uqE7eFE.jpeg

Shoeless

07-19-2021, 06:00 PM

Did a bunch more research and reading on the CTS-V alternator and after hours of research I still couldn't find the pin out for the two pin alternator that I have. What I did find out was that one pin is supposed to accept a 5V PWM 127 Hz variable duty cycle from the computer (this is the turn on signal) and the other actually outputs a 5V PWM signal to the BCM (Body Control Module) (this is the state of alternator). So I cut up the plug lead, being careful to not take up too much wiring as I'd need to rewire this once I figure this all out, and ran leads from each pin up to the cockpit so I could run the engine and swap out leads to see which one is putting out a PWM signal. Now I know for sure which pin I need to send a PWM signal to.

https://i.imgur.com/jDjXsRE.jpeg

At this point I simply swapped leads on the plug from the ECU to send the PWM signal to the proper pin, but nope, still wouldn't turn on properly. By now I was kind of scratching my head a bit, but needed to figure this out. I decided to purchase a 12V to 5V converter, and PWM generator, and a box of a wide range of resistors. Now I can swap out resistors that tie the 5V and LowSide switch output from the PWM generator to find the perfect 5V PWM signal that would actually turn the alternator on. Her'e a pic of the setup and then testing resistors out at the GTM. For reference when I built the wiring harness I used a 100K ohm resistor. Testing this resistor on the below setup only output a 4.99V signal and was not enough to activate the alternator.

https://i.imgur.com/AL4L0rk.jpeg

https://i.imgur.com/B9DsQkN.jpeg

After some trial and error I landed on a 1K ohm resistor and hooked up the PWM generator and fired the GTM up. BAM THE ALTERNATOR CAME TO LIFE!!! You can see on the digital dash, it was finally outputting over 14V.

https://i.imgur.com/QsJyQzQ.jpeg

https://i.imgur.com/VOvrXvM.jpeg

Now that I know a 1K ohm resistor works on the PWM generator, I rewired the jumper plug from my engine harness to the alternator. Fired the engine up and sure enough, it is working just as it should. I could adjust the duty cycle in the ECU software and watch the output voltage change as it should. For now I'll leave the table at 26 (equating to a duty cycle of 74)

https://i.imgur.com/wfhvbKW.jpeg

https://i.imgur.com/Rqvgv9A.jpeg

Now what I'll do is put a warning in the dash software to tell me if the voltage ever drops below 14V (alternator not functioning as intended, but could still output the default 13.6V) and program it to give me a custom message at the bottom of the screen and flash the yellow LED on the left side of the dash. I can also program it if it drops below 13.0V (i.e. alternator fried) to flash the red LED on the right and change the whole screen to a warning screen.

Now that I got this figured out, maybe I can finally sleep tonight LOL. I haven't slept well for the last week scratching my head on this one.

crash

07-27-2021, 10:08 AM

Very interesting in regards to the carbon fiber case. I worked on a hybrid project where one of the other teams tried to use a carbon fiber enclosure for the batteries. At one point a couple of the batteries terminals touched the carbon enclosure and the thing almost immediately caught fire. Luckily it wasn't in the car at the time. True carbon will conduct electricity VERY well. Hope they have that sorted.

Hey guys,

Just over three months ago, my Braille B3121 battery stopped holding a charge and I sent it in to Braille for warranty consideration. I was told there were some delays due to covid, but hopefully it wouldn't take too long to get in the components they needed to build up a replacement. Every couple of weeks I would check in with Braille via email and would always get a reply within an hour or two from Tori letting me know that unfortunately there were no updates. After a couple months of this she offered up if another of their AGM offerings would work for me. Unfortunately that wouldn't work, but I started to look at there lithium offerings.

I looked at one model in their Green-Lite Lithium line and fired off several technical questions, and even some follow up questions on the B3121. I received a response from Braille's tech department that the model I was looking at wasn't designed for high displacement engines, and that even the load my LS3 would place on a B3121, would cause its life to be cut in half. The tech support guy recommended for an application like ours, an i34RX lithium would be perfect. He also threw in there if I wanted to stay with a battery the size of the B3121, I would have to step up to the ML30C. This is their most powerful lithium battery available and has been used by the Corvette Racing team for 11 years, Ford with their GT program for 4 years, the Lexus RC-F GT3 program, and many more. Braille was even running some specials for a lithium specific charger as a package selling with the ML30C.

Well, after thinking this over a bit, I jumped in and said let's do it. Tori applied the full warranty cost of my B3121 against my new order and put the order in. This was on Tuesday, and today, my package arrived. I did not expect such a timely order, but boy was i happy. I knocked off work early, installed the battery, and fired the GTM up. Holy crap, it was literally a bump of the key and she came to life. Braille claims a full volt higher than lead cell and less voltage drop while cranking. Not to mention several other benefits over the old antiquated lead cell batteries. This thing is literally a work of art encased in its very own carbon fiber case.

Since I am running the newer CTS-V alternator, I also checked in with Braille for the proper charging voltage as I can change that via a PWM signal from my standalone ECU. This battery is also standard charging system friendly and works great with anything from 14.0 to 14.8 Volts. So I plugged in the laptop to see what voltage was being put out, and was a little stumped that it was only outputting 13.6V. I tried changing the duty cycle in the software and there was no change in voltage output. After some research, I discovered I have the alternator hooked up incorrectly and the alternator will default to 13.6V if its not set up correctly. So I either have it hooked up incorrectly or my PWM signal from my ECU is incorrect. I'll have to pull out the bench o-scope to test the output from the ECU and correct the incorrect wiring that I know I have. Hopefully this will solve my charging voltage issue, and I'll stick a fork in this and be done :cool:

https://i.imgur.com/UCURE1g.jpeg

https://i.imgur.com/uqE7eFE.jpeg

Shoeless

07-27-2021, 01:52 PM

crash

07-27-2021, 03:55 PM

I bet that was quite the scare for that team.

Yeah, I bet it was. I was in the Diesel Engine Controls Team and the fire happened in another building. We heard about it though.

Shoeless

07-27-2021, 04:49 PM

Yeah, I bet it was. I was in the Diesel Engine Controls Team and the fire happened in another building. We heard about it though.

I’m sure they have this sorted for this setup. I wouldn’t imagine Corvette, Ford, and Lexus teams would run these with a risk like that.

Shoeless

08-01-2021, 08:25 AM

Working on some odds and ends on the GTM. Next up was the install of the rear view camera mirror/monitor. Brian B. fellow GTM owner gave me the model number of the camera monitor he picked up and shared with me the roll bar clamp that he used. The idea was to mount the mirror high and out of the way from the view out the front of the GTM windshield, but still allowing the front camera on the mirror to function. The model is a AUTO-VOX V5PRO and picked it up off Amazon. I had to make a round spacer and get some longer hardware for the mirror to mount to the roll bar clamp. Scuffed everything up and painted black to match the roll bar. Overall this came out really nice.

https://i.imgur.com/Wrkzmrx.jpeg

https://i.imgur.com/nyo0epM.jpeg

https://i.imgur.com/3cKNTgZ.jpeg

Shoeless

08-02-2021, 07:25 AM

Time to start working on the Stance Air Cups install. Like many others, I opted for the tankless setup and started to place all the components in the front of the GTM. First up was installing the cups on the coil overs and checking the ride height in the front. With the ride height set roughly where it needs to be (4.5" from the front square frame tube just below the front of the door) and then jacking the car up to simulate full droop, you can see in Pic 3 I'd have nice gap to deal with between the spring and the retaining ring. Adjusting the sway bar up as far as I could (still having 1.5 x the diameter of the turn buckle threads engaged, Pic 4 and 5, it looks like I have enough of a gap to clear a helper spring. Unfortunately going through the travel its a little too close for my comfort, especially knowing a fully compressed helper spring (Swift ones similar to what I used in the rear) is about 0.9" with retaining ring and that is just too close to the roll bar components. With that I've opted to order 7" springs (currently I have 8") to give me the extra clearance I need for a proper helper spring. Pic 6 and 7 show where the relay, valve, pump outlet and pump will be located. Its a bit cluttered, but each of the yellow dewalt clamps are holding the components. The pump will be located under where the A/C blower relocation piece is and attached right to the frame rail. Once I get this mounting plate cut and mocked up, I'll probably get it powder coated the same silver hammertone as all my other accent parts.

Pic 1
https://i.imgur.com/vlJ5VQG.jpeg

Pic 2
https://i.imgur.com/8MGVuMB.jpeg

Pic 3
https://i.imgur.com/scWiaIP.jpeg

Pic 4
https://i.imgur.com/Njnh566.jpeg

Pic 5
https://i.imgur.com/wOmtwXv.jpeg

Pic 6
https://i.imgur.com/zU5BFQH.jpeg

Pic 7
https://i.imgur.com/YIhemal.jpeg

VRaptor SpeedWorks, LLC

08-02-2021, 08:20 AM

Nice Progress! That "mirror" looks like it should work out really well there.

cgundermann

08-16-2021, 05:27 PM

Very, very nice setup. A must have…

Chris

beeman

08-17-2021, 08:52 AM

No fun having that sway bar give you trouble with the suspension components.
What's everyone's thoughts on a front sway bar for a street GTM? It will definitely make the ride more harsh, I wonder if you will ever see the benefit off the track.
I am not currently planning on installing a front (or rear for that matter) sway bar on my GTM, will be 90% street, 10% track or so...

cgundermann

08-17-2021, 09:52 AM

Different suspension geometry, but my older MK4 does not have sway bars and has exceptional road manners. I know they are offered on newer Cobra kits and there have been a number of threads on whether they are warranted for a street Cobra. Be interesting to hear how the experienced GTM builders feel…

I’d rather have the capability for a front lift.

Chris

crash

08-17-2021, 10:08 AM

Let's put it this way...many people feel a Limited Slip Differential is a requirement in a GTM. I disagree. I would put a front anti sway bar WAY up on the list as opposed to a LSD. To each their own, but IMHO there is a reason that just about every production car these days have front and rear anti sway bars.

Shoeless

08-17-2021, 10:26 AM

I'll get the front suspension all sorted out. I'm so used to running into hiccups on this build, I almost expect it any time I do something major.

Amazingly enough when I was in Costa Rica this last week I got notifications on my Ring cameras about a delivery at my house. The new shorter springs were supposed to be a 1.5 month lead time when I ordered them. Well, somehow that was completely wrong and they shipped immediate from the manufacturer when I placed my order on Summit. Thankfully we had my wife's daughter checking in on the house while we were out of the country. I had her open the box and sure enough it was the shorter springs. Sweet!!! I got the helper springs on order yesterday and should be here in a week as well.

For alignment purposes, I also got a lead on 190 lbs of rubber coated dumb bells to put in the driver seat to mimic my weight. Hopefully the guy still has them today and I can go pick those up.

I also opted for a LSD in the Mendy I got. Maybe overkill for me, but it wasn't that much more money when I ordered it.

I think the only track time this car will see is more of fun track run days. No serious hard core racing, but I do want to get on the track to really let her loose. Down near me in FL is the Palm Beach International Raceway where they host supercar days. I will definitely be taking full advantage of those days :cool:

beeman

08-17-2021, 11:33 AM

there is a reason that just about every production car these days have front and rear anti sway bars.

I attribute that requirement to the soft suspension in most production cars vs the GTM's firm suspension, light weight, and low center of gravity. I also haven't felt my FFR roadster needs a sway bar even on the track. Not to say that I won't ever add a sway bar to the GTM, but you definitely pay for a sway bar with a harsher ride on public roads.
Sorry to divert your thread, Sean

Shoeless

08-17-2021, 12:06 PM

I attribute that requirement to the soft suspension in most production cars vs the GTM's firm suspension, light weight, and low center of gravity. I also haven't felt my FFR roadster needs a sway bar even on the track. Not to say that I won't ever add a sway bar to the GTM, but you definitely pay for a sway bar with a harsher ride on public roads.
Sorry to divert your thread, Sean

No need to apologies at all, I really enjoy some of the side conversations we have. Its more opportunity for me to learn new things I may not have much knowledge on.

I do remember seeing on Ted's website that running the front sway bar allows for softer springs in the front. I've only ran around the neighborhood and up to the park less than a 1/4 mile away from the house, so I haven't really got much driving time. Not to mention my alignment is WAY off and stupid unstable over 25 mph LOL.

Shoeless

09-12-2021, 09:34 AM

Not a particularly fun day on the GTM today. I had noticed a leak from my Mendy transaxle not so long ago and unfortunately need to pull it out to investigate further. At the moment it looks like the front seal that is behind the throw out bearing, but working closely with Ian on troubleshooting and correcting this issue.

https://i.imgur.com/ThcZsPd.jpeg

https://i.imgur.com/aFla9nC.jpeg

https://i.imgur.com/CWZR2JT.jpeg

SteveE

09-13-2021, 09:09 AM

That in no way can be any fun, hope that you are able to sort it out.

crash

09-13-2021, 11:29 AM

At least you found that before putting the body on. Much easier now than later.

Shoeless

09-13-2021, 11:35 AM

At least you found that before putting the body on. Much easier now than later.

I actually had the body temporarily mounted. Drilled out a handful of rivers and pulled it right off. It was definitely a long tear down day, but glad I got it pulled to start the troubleshooting. We’ll get this all sorted quickly :cool:

KGTM

09-14-2021, 09:55 PM

why leak with new tranny?

Mostafa

Shoeless

09-15-2021, 07:41 PM

why leak with new tranny?

Mostafa

I got to do a little more investigating and I'm very confident I have found the area of the leak. The "why being new," I'll chalk that up to likely a bad seal. Was kind of upset at first, but I can't stay upset for ever, I just need to fix it. The nice thing is I have been in direct contact with Ian and I am very happy with the level of support he is giving me. Shared several emails with pics and questions, and Ian has taken the time to answer every single question and help me find the issue. He is also sending out a replacement seal and gave me some instructions on how to get this out and put the new one in.

Here are some more pics of the investigation. First pulled the throw out off. Was a little tricky, but once I loosened up the fitting for the breather and the clutch line input, it dropped right out. From there I looked at the seal itself and you can see the green part of the seal was kind of pushed out of the way a little on the left and right bottom. In the fourth pic you can see an area I circled in red as the main suspect area. So from there I cleaned all the leaking fluid off and let it sit overnight. Sure enough first thing in the morning you can see the fluid starting to seep out right from that red circled area from pic 4 in the last pic. This seal is definitely the culprit and looking forward to getting the new one delivered, this one pulled out, and the new one replaced. I'll post more of that whole process as I go along.

https://i.imgur.com/Vw5FvrY.jpeg

https://i.imgur.com/jetXVNN.jpeg

https://i.imgur.com/5O45haR.jpeg

https://i.imgur.com/IFMDSl3.jpeg

https://i.imgur.com/iKJUF1Q.jpeg

jamesfr58

09-18-2021, 07:28 PM

Shoeless

09-18-2021, 08:02 PM

Sean

Great to see how far you have gotten on your GTM. Finally got back to mine after almost a year with very little done, but you have really done a lot. Looks good and I feel for you I had to pull my transaxle after installed to correct a problem not an easy chore glad you found the problem.

Hey James,

Welcome back. I have made a ton of progress and other than this leaking transaxle issue, I'm very happy with the progress of the build. I put the new seal in today and still have the transaxle tilted up to let the silicone dry. I'll have some follow up pics to post shortly.

crash

09-21-2021, 01:08 PM

Just looking at pics and I notice the upper hole in pic 3 looks a little odd. You may want to check those threads and blow out the hole with compressed air.

Shoeless

09-21-2021, 01:52 PM

Just looking at pics and I notice the upper hole in pic 3 looks a little odd. You may want to check those threads and blow out the hole with compressed air.

Good catch. I just went and double checked it, I got it all cleaned out.

Shoeless

09-24-2021, 07:47 AM

Hey guys,

Over the last week I have been working on this seal replacement and was very thankful that Ian sent me two seals. The package from Ian arrived on Saturday and Ian was nice enough to send me an email on Saturday, as he was keeping an eye on the tracking noting it was delivered, with some additional pointers on replacing the seal. The first seal I installed that day and left the transaxle tilted up over night so the silicone could dry. After 24 hrs I dropped the transaxle down flat and let it sit to see if I fixed the issue. Unfortunately less than 24 hrs later and it was already leaking again. I was a little bummed out, but I had a second seal and needed to give it another shot.

When I removed the first replaced seal, I spent a lot more time cleaning the area and looking for possible nicks or anything that would cause issues on the second replacement seal. I noticed two VERY small nicks on the chamfer that leads into the sealing diameter, probably caused by me removing the first seal, that I needed to clean up a bit. I took some 2000 grit sandpaper and lightly worked this lead in chamfer ever so slightly until perfectly smooth. I cleaned the area out with alcohol and blew some compressed air to dry it out. Since the first replacement seal leaked I put a very small bead of silicone (Permatex 82180) on the lead in chamfer of the housing and also put some on the OD of the seal. I also put a small amount of grease on the ID of the seal where it mates to the output shaft. Using a tool Ian sent me, I lightly and evenly tapped the seal in place to seat it, then flipped the tool over and tapped the seal perfectly flush. It does not take much force at all to install this seal, may have also been my downfall on the first one, so this second time I lightly tapped the tool with a rubber hammer. The seal seated perfectly and I cleaned up excess silicone. I also left the transaxle tilted up for a couple days before I dropped it down flat. So far, its been about 36 hours since laying it flat and no leaks. I think I might have this taken care of. I'll probably work on installing the transaxle back in the GTM this weekend and get everything all put back together. Then I'll put some miles on it driving around the neighborhood (the neighbors love me :cool:) to see how she holds up.

Below are the pics of the last seal install and some general comments.

In order to remove the seal use a flat head screw driver to puncture the front of the seal and pry it out. You can see here I was a little aggressive when I punctured the first seal as I dented the back wall. Thankfully nothing seals on the back wall, so this was not an issue.
https://i.imgur.com/YE5YNu3.jpeg

https://i.imgur.com/XMOuYxA.jpeg

https://i.imgur.com/DistMU9.jpeg

Custom tool that Ian shipped me to install the seal.
https://i.imgur.com/YLhA89y.jpeg

Final replaced seal.
https://i.imgur.com/D2PZu9C.jpeg

jamesfr58

09-24-2021, 11:50 PM

Shoeless

09-27-2021, 07:12 AM

Sean

One thing I have discovered building the GTM is you end up making a lot of tools no one would ever need except you do to build this car. Glad to here it sound like you got if fixed hope say no leaks....

Hey James,

After my dad passed away when I was a lot younger, I eventually inherited what was left of his tool box and tools from his entire career as an auto mechanic. I started working for him when I was 11 and worked my way up to rebuilding our first motor together when I was 15. Over the years he always made these weird looking one off tools. They had a very specific purpose on an individual car and made life very easy for that particular job. This tool reminds me exactly of that. I still have a few of these tools, but have zero clue what they are for. I'll likely never use them, but I'll never throw them out.

jamesfr58

09-27-2021, 01:12 PM

Know what you mean I have a few of them form my father and my father-in-law who has passed away and I have no idea what hey were used for either, still in my tool cabinet and will be passed down to my kids and I will let them try to figure it out because I still haven't....

Shoeless

09-29-2021, 10:36 AM

Hey guys,

I was able to reinstall the transaxle this past Friday and Saturday and get everything all buttoned up to allow me to get some miles on the GTM to see how the seal repair would hold up.

https://i.imgur.com/HiDuaMZ.jpeg

https://i.imgur.com/s6UwlOm.jpeg

Last time I took the GTM on the road, it was wildly unstable over 25 MPH, so before I hit the road I did a little change on the toe adjustment. After some slower runs around the neighborhood, stopping periodically to check for leaks, everything looked good to stretch her legs a bit and hit the local road. I was able to get up to about 55 mph before it got a bit unstable again so I made some runs up and down the road to get all the fluids up to temp and again checked for any leaks. So far so good, no issues. So I hit the road again and did the bedding in process for the Wilwood brakes. Everything turned out great with me only needing to change the bias a bit to the front. My rears would lock up before the fronts, so I'll do a little adjustment there and put a tad bit more bias to the fronts and retest. After putting about 20 miles on the car, I pulled right back into the garage to put it on the jack stands to take a very close look underneath. Success, no leaks and no issues!!!! I'll be keeping an eye on this, but all indications point towards me addressing the leaking seal on the transaxle.

crash

09-29-2021, 11:37 AM

Shoeless

09-29-2021, 04:08 PM

Glad to hear it is all good now.

The engines and the transaxles are both very complicated pieces. People get used to perfection every time in our society, but that usually isn't reality. I know Mike and Ian and all the guys at Mendeola work very hard to get every transaxle out the door in perfect operating condition, but when that doesn't happen they also bend over backwards to fix any issue. At least that has been my experience and it looks like that is what happened here as well. You won't get that type of service from a wrecking yard with a used Porsche transaxle, or even from GM if there is an issue with a new crate engine. Just ask Shane. LOL!

You are spot on Crash. We all wish the world would be full of perfection and no issues, but that's simply unrealistic, especially building a car like this. Ian was absolutely amazing to work with on fixing this issue. He answered every little question I had along the way, with multiple emails daily and even on the weekend for this repair. I'm sure some of my questions were VERY elementary, not knowing how to even approach performing this repair myself or if I was going to have to return the unit to California, but Ian totally took care of me. I could not be more pleased with how this turned out. I had an issue, Mendeola was all over it, and the problem looks to be completely addressed. Massive kudos to those guys.

Oh yea, Ian even threw is a couple custom Mendeola shop towels in the package with the replacement seals :cool:

VRaptor SpeedWorks, LLC

09-30-2021, 08:07 AM

Shoeless

10-01-2021, 07:35 AM

Glad you got things fixed! Yeah....not many people understand the hours that need to go into cars like this to get them right. Like I tell my customers.....yes, I could probably build a GTM in 500 hours, but it would be anything you'd want to be seen in public in and you might not make it all they way around the block before something fails.

Thanks Shane!! Hopefully I was able to explain and walk everyone through the repair process in enough detail that anyone could pick this up and perform it if needed.

Shoeless

10-02-2021, 09:45 AM

Hit another fun milestone yesterday. The GTM snuck out and made it to the gas station to fill up followed by another 20 or so miles of the engine break in. Thought I'd also throw in a walk around video.

https://i.imgur.com/RZTn1dm.jpeg

https://youtu.be/4yr87siBf2w

dlud

10-02-2021, 11:59 AM

That engine really sounds good! Well done.

Shoeless

10-03-2021, 03:03 PM

So something happened yesterday that I totally didn't expect. Since photo bucket started charging for posting pics, I've been posting all my photos to Imgur so that I can then share them here easily. I post them on my phone, then simply create my posts here. So I posted the walk around video above and pic at the gas station and it took off like crazy. Last count today it has over 93,000 views, hundreds of comments, and basically broke Imgur for the day LOL. If this is any inclination to how much attention a GTM will get out in the real world, I can't wait for this build to be done to fully enjoy it.

https://i.imgur.com/av3XpJF.jpeg

Shoeless

10-03-2021, 04:45 PM

Next up is working on the alignment. This was also one of the classes I took online from the same company I did the tuning and wiring classes with. I picked up a string alignment kit, caster gauge, turn plates, camber gauge, and ordered a set of corner scales. I've got everything on hand except the corner scales as they were on back order. I ordered them from Speedway Motors as they were giving away a free carrying case for the scales. i was hoping to save a few bucks, but if they are backordered much longer, I may get the kit from Summit.

First step to getting an accurate alignment is setting the flat patch. Start out with blue painters tape marking the location on the garage floor where you want to perform the alignment. Then take a piece of extruded aluminum and two sockets of equal height. Place the sockets in the middle of the tire location, place the aluminum beam on the sockets, and then take the digital camber gauge and check level left and right. If you find the level left and right is off, you can use vinyl flooring tiles that are 1.2 mm thick to make it level. Repeat this for the rear tires and now the left to right for the whole car is level. Then check front to back. I actually ran out of tiles so I couldn't get a front to back level this weekend, but not to worry, I don't need that for initial camber and toe work. Once I get the scales and work on corner weights, you will need 100% level flat patch, left to right and front to back.

https://i.imgur.com/dhCZXbe.jpeg

https://i.imgur.com/ggUlnEt.jpeg

https://i.imgur.com/OJWP0tO.jpeg

I took initial camber measurements on all four corners and then moved on to checking and adjusting toe. Setting up the string alignment kit was very straight forward. Took me about 30 minutes to set it up and zero/calibrate. I recorded the setup in my notebook, making it quicker setup next time, and then went on to toe measurements. I also threw a rachet strap on the steering wheel so that it will be held in a constant location through the process. No wonder this thing was so unstable over 45 mph, all four corners were WAY toe in. No worries, I set the front to 1/8" toe in and the rear to 1/16" toe in per Crash's recommendations.

https://i.imgur.com/IifuPes.jpeg

https://i.imgur.com/BGmijCO.jpeg

At this point, its worth it to go take it for a drive and see how well I'm doing. Overall I'm VERY pleased with how well its handling. The steering wheel is centered, the GTM tracks straight, and the handling at higher speeds is amazing. I was able to get up to 70 mph on the side road and handling was EXCELLENT.

https://i.imgur.com/LYyda3A.jpeg

crash

10-04-2021, 03:02 PM

The attention thing is good most times, but when you have to get something done it can get tiresome. If it gets too much for you I suggest you make a little card that explains the basics about the car and FFR and kindly hand them out when people ask about the car. We have done that at races and it not only frees up your time, but is a great advertisement for FFR. FFR used to have some little brochures to hand out. Don't know if they still offer those or not.

Shoeless

10-16-2021, 06:28 PM

Hey guys,

I spent some time in the garage today focusing on the front alignment. The rear was quite a bit easier since only the front can adjust castor. Thankfully I think things really fell into place for me with a couple minor changes from my first guess with Crash's shim setup. First up is getting your flat patch set again in the garage. I picked up some more vinyl tiles so that I could set the front to back and also left to right flat patch. Took a few of the extra tiles I bought and now I have a 100% flat patch to work with.

Next was placing the turn plates in location for the front and get the wheels prepped with the custom machined bung I had made at a local shop installed. Obviously these wheels are not magnetic so this allows me to attache the castor gauge. To check the castor, turn the wheel 20 deg in the direction of that side wheel to start. If checking castor on the right, turn the wheel to the right 20 degrees and then zero the gauge. Then turn 40 degrees to the left and read the gauge. I was having a little trouble with the turn plate on the right, due to not much weight on that wheel, thankfully I was able to read the turn plate on the left while measuring the right.

https://i.imgur.com/6ZGwnQm.jpeg

https://i.imgur.com/ULNtnJP.jpeg

https://i.imgur.com/caoS91M.jpeg

https://i.imgur.com/9zLaf67.jpeg

After making a couple changes, I ended up with the below alignment numbers. Took it for a test drive and realized my steering wheel is a bit off so I need to revisit the front toe. Overall it drove really well and I put a few more miles into my break in period. This engine is going to be a beast, I barely touch the pedal and this thing takes off like a rocket.

Front Castor Left: 7.33
Front Castor Right: 7.25
Front Camber Left: -0.3
Front Camber Right: -0.5
Front Toe Left: -1/8
Front Toe Right: -1/8

Rear Camber Left: -0.3
Rear Camber Right: -0.5
Rear Toe Left: -1/16
Rear Toe Right: -1/16

beeman

10-16-2021, 10:10 PM

Nice work! I don't think I've seen front caster #s anywhere near that without adjustable UCAs or moving to the upper mount locations?

Shoeless

10-17-2021, 06:38 AM

Nice work! I don't think I've seen front caster #s anywhere near that without adjustable UCAs or moving to the upper mount locations?

Thank you!!! When I first got the drivers side castor number I thought it was high as well. Then I made the same needed adjustment on the shims on the passenger side to bring the camber in and got a similar number on that side. I’m wondering if the PFAD bushing kit I installed moved the upper mounts rearward at the frame attachment point compared to the OEM bushing mounts.

Shoeless

10-17-2021, 01:24 PM

I need to work on mocking up the interior buttons and plug panels and get them all wired up, so I printed out a few panels on my new 3d printer (Creality CR-10). I should have bought one of these printers years ago. The possibilities are truly endless.

The button panels will just be temporarily riveted to the frame to hold them in place while I work on the wiring and the plate with the UBS panel will be made out of carbon fiber and mounted to the left side of the tunnel. I ordered up another billet button for my stance air cup kit so all the buttons match.

The last pic is a two piece mount I came up with to hold an air fitting to pass the stance air line through the sheet metal. The idea is the base will be riveted to the sheet metal and the top piece is epoxied to the bottom to hold it in place. I was able to create a pocket in each piece to help with the strength of holding them together. I'll mount this next to the brake line and wheel speed sensor pass through so make it look clean. I'll post up pics when I'm done mounting these.

https://i.imgur.com/0s9Wi8X.jpeg

https://i.imgur.com/NL1i4yX.jpeg

https://i.imgur.com/FeH8FxQ.jpeg

VRaptor SpeedWorks, LLC

10-18-2021, 08:19 AM

Very nice! Love the printed parts!

On your alignment numbers, are you running 1/8" toe on each side?....for a total of 1/4" toe in?

Shoeless

10-18-2021, 09:03 AM

Very nice! Love the printed parts!

On your alignment numbers, are you running 1/8" toe on each side?....for a total of 1/4" toe in?

Thanks Shane!!!!

Yes, -1/8 toe each side for a total of -1/4. Is that too much?

Maybe I misinterpreted some previous posts that say 1/8 toe in the front as total toe, 1/16 per side. Same on the rear, I did -1/16 per side for a total rear toe of 1/8. Thankfully toe is easy enough to adjust.

crash

10-18-2021, 10:28 AM

Shoeless

10-18-2021, 02:30 PM

Just so you are aware, the weight of the body is significant. I am assuming that you did finished ride height on the frame before alignment? If so, then after all the other stuff gets mounted you should be able to adjust the springs, get what your current ride height is, and have the alignment come back in to what it should be. Remember that these numbers are static at ride height and will change, sometimes significantly, when the suspension is in motion. Reducing bump steer as much as possible is recommended.

I absolutely set the final ride height before starting any of this alignment effort and fully expect to need to revisit for minor adjustments at the end if I was off a little on the ride height. I even got my set of corner scales the other day, so I'm very interested to put them to use and see where I'm currently at.

Bump steer adjustment and corner scaling will be next. After all that, its a little repetitive going to back to check everything else to make sure final numbers are where I want them to be.

I will say overall this has been a pretty time consuming process, but I wanted to learn it from start to finish so when I take the car on the track and feel what it is or isn't doing, I can ultimately make the adjustments myself and then see what my adjustments do.

Crash's alignment shims have been a BIG help. Once I set the front left corner, I was able to make predictable changes to the other corner and land where I needed at the end.