Project Deimos: An LS '65 Coupe Build: Engine no longer overheating!

[JimStone]

It's a good thing I'm building a car instead of a boat, because I've had so many leaks lately that this thing would have sunk by now.


The massive coolant leak from the poorly assembled water pump has been fixed. I was able to successfully pressure test the system to 20 psi (4 psi over what my radiator cap is rated).







Next, I tried bleeding the power steering system but could not get the air out. I realized I had a small leak at one of the steel fittings on the high pressure hose. I did make that hose, but I don't think it was my fault because it was leaking from one of the fitting's tube/body and not from the hose end part that I assembled. I still had the hose from the FFR power steering kit. It was about a foot too long but I made it work. Put some basalt fiber sleeve over it to match some of my other hoses







The next leak is completely my fault, and I'm still sick to my stomach over. I did what I've been warned a million times not to. I was tightening down the nut on the positive battery lead when my wrench grazed a nearby stainless brake line (and yes, I stupidly had the neg cable already hooked up). There was a spark and immediate deluge of brake fluid everywhere.






I'm going to try to repair it in place without taking the whole line out. But I honestly don't even want to think about it right now. Very disappointing







There has been some good news though.

I finished my heat shields made of dimpled aluminum stretched over 0.09 inch aluminum sheet, thern I cerakoted them with high temp V-series, and installed with spacers to give a 3/8 inch air pocket behind.

I also Cerakoted the headers and side pipes





I decided the heat shields were necessary after learning more about aluminum panel heat/sound insulation, and realizing I had probably made a mistake with my footbox linings. I had lined them with foil covered butyl as the first layer against the panel. Then closed cell foam, mass loaded vinyl, another thin foam, then vinyl upholstery.

Well, I learned butyl has a relatively low melting point (~250 F) but will start to droop at even lower temp, around 150 F. Thus the heat shields. Hopefully they work.






[Continued next post]

[JimStone]

[Continued]




I filled the engine with oil (no leaks!) and made some good priming, no-spark pulls with the starter. It was great to see oil pressure on the gauge.






The spark plug wires on the LS nearly touch the headers, so I wanted heat shield sleeves. But I wasn't happy with what I found online. I ordered some pre-made ones on amazon but was disappointed by how stiff they were and didn't like the look.

I made my own by first putting a silicone coated fiberglass sleeve over the wire, then covering that in basalt fiber sleeving. It's much more flexible and looks good





I'm darn close to starting this engine (finally!)

I think I only need to get the front wiring harness hooked back up (for the fan), put the side pipes on, do the initial setup on the Terminator X Max, and get some gas.

First start on MLK Day???

[PNWTim]

Jim - your spark plug covers look really nice and I am sure they will work but keep an eye on the boots. In the future, if needed, you can also purchase hi temp spark plug wires with ceramic boots. I have these on my LS and they work great.

https://www.holley.com/products/igni...rk_plug_wires/

[JimStone]

Jim - your spark plug covers look really nice and I am sure they will work but keep an eye on the boots. In the future, if needed, you can also purchase hi temp spark plug wires with ceramic boots. I have these on my LS and they work great.

https://www.holley.com/products/igni...rk_plug_wires/

Thanks Tim. I wasn't aware of those type of wires/boots. Mine are what was shipped from Blueprint, which I'm sure are "just okay" quality

[JTG]

That's quite the update Jim! I'm impressed with your persistence in working through all these detours and details. We'll be certain to share our leaks when we have them

[460.465USMC]

Those backsteps can feel defeating. Ask me how I know. But first start will be all the sweeter as you solve them one by one. Keep up the great work, Jim! We're cheering for you, and looking forward to hearing that beast wake up and rumble!

[JimStone]

Thanks for the encouragement on the leaks, guys


So, no First Start on MLK day. New plan is for this Saturday






Put some fuel in the tank and ran the fuel pump. Had a leak at the fuel regulator where I had a stainless hard-line connection to the firewall bulkhead fitting. I didn't feel like remaking the hard-line, so quickly put together a PTFE AN fuel line with leftover parts






Leak fixed, I set the regulator to 58 psi and it held pressure fine.

I used the 87+ Ford fuel tank sender setting on the Speedhut gauge, which was the best match to my pre-installation measured Ohms of 12-142. I put 5 gal of gas in and it's showing only just past 1/8 tank, so I may need to adjust that later






Put the side pipes on and installed the hangers. I had Cerakoted them earlier. Turned out okay, but I had some scuffs around the collector flanges, so I may try to touch that up with an airbrush later.





Installed a fuel pump push bottom switch on the trans tunnel cover. Was getting tired of the fuel pump running when testing other electrics and needing to take in/out the fuse.

Also did the basic initial settings for the Terminator X on the handheld device.. I've been learning a lot from ChatGPT about some additional settings to input before First Start to get a better idle, based on my cam specs. Need to hook up a laptop for that, and download the Holley software






You can also see where I made a hole in the trans cover panel for a cup holder. I can't leave anything well enough alone, so I put blue LEDs around the bottom





That's it for now. Next update: hopefully after a successful fire up of this engine

[PNWTim]

Looks to me like you are getting pretty close. Just a couple of comments. First, I think you need at least three or four more wires behind your dash to even out the look . Second, I like the additional lighting anywhere you can put it. It's one of the great things about LEDs in my opinion.

On a side note, I am surprised your fuel pump was on continuous run. I don't have any familiarity with the Terminator X but I know with the GM PCM it's similar to the Coyote setup. It primes the fuel system for 1-2 seconds and shuts off unless the engine starts. Either way, looking forward to the video this weekend. Good luck!

[lewma]

Get that thing started!!!

[JimStone]

[

Looks to me like you are getting pretty close. Just a couple of comments. First, I think you need at least three or four more wires behind your dash to even out the look . Second, I like the additional lighting anywhere you can put it. It's one of the great things about LEDs in my opinion.

On a side note, I am surprised your fuel pump was on continuous run. I don't have any familiarity with the Terminator X but I know with the GM PCM it's similar to the Coyote setup. It primes the fuel system for 1-2 seconds and shuts off unless the engine starts. Either way, looking forward to the video this weekend. Good luck!

You're not suppose to look at the wires! So embarrassing. I need to censor out that rats nest in future posts

You're right about the Terminator X being able to control the fuel pump. I had already wired the pump according to the FFR manual, so when I installed the Terminator X a year later I naively thought "what's the difference?" Now I know.

I could have switched it over, but I like the button now. More things to press in the ignition sequence, like a racecar, or a fighter jet.

Get that thing started!!!

On it Mark!!

[jemorgan3]

does the terminator x not need a fuel pump speed controller? Im planning on running a Aeromotive 525lph in tank pump with an Aeromotive fuel pump speed controller to modulate the pump. would be nice if the terminator x ecu does that for me!

[JimStone]

does the terminator x not need a fuel pump speed controller? Im planning on running a Aeromotive 525lph in tank pump with an Aeromotive fuel pump speed controller to modulate the pump. would be nice if the terminator x ecu does that for me!

Whoa, what are planning that needs that big of fuel pump?

So, your question about fuel pump modulation opened a can of worms. I had never read in the forum of someone using a fuel pump speed controller. However, most builds on here have smaller pumps than you. I did some research and there does seem to be an ability for the Terminator X to act like a PWM, but the discussion went way over my head.

For my size fuel pump (340lph), it doesn't seem needed.




And Tim,

After reading more, I am going to switch over to the Terminator X handling the on/off of the Fuel pump, like you suggested. It's a safety thing. If the car crashes, the way I have it the fuel would keep pumping, perhaps spraying from broken lines onto hot headers and pipes.

My push button fuel pump switch is simply in the ground trigger loop for the relay. So I'll just hook up the Terminator X green wire to my push button and all will be well

[jemorgan3]

My previous fun car was a 5th gen ZL1 Camaro, 18lbs of boost from the OEM LSA blower... that blower can go from a vacuum to 18lbs at very low rpm with a high load, so having enough fuel instantly is pretty crucial. From owning that car, I have a paranoia about fuel pressure and supply. With injectors, you absolutely want something that isnt to small, but also not oversized either. With a pump, however... There isnt a reason not to go a bit overboard with it!

From the research ive done, the terminator system can command a pump on/off, but cannot modulate its duty cycle. Running a fuel pump at its maximum capacity 100%W of the time will work, but will also reduce its lifespan. A true PWM fuel controller will match the duty cycle of the pump with the demand. Just makes it a more efficient system. I would argue that any aftermarket fuel pump will benefit from a fuel controller. will it run without one, yes. Will if fail earlier, also yes.

To answer your question, my coupe is getting a forged LS3 based 416 with a focus on RPM. But when the 525lph pump is only $100 more than the 340lph, why not buy the insurance (or enable the addition of an LT4 blower later).

[JimStone]

My previous fun car was a 5th gen ZL1 Camaro, 18lbs of boost from the OEM LSA blower... that blower can go from a vacuum to 18lbs at very low rpm with a high load, so having enough fuel instantly is pretty crucial. From owning that car, I have a paranoia about fuel pressure and supply. With injectors, you absolutely want something that isnt to small, but also not oversized either. With a pump, however... There isnt a reason not to go a bit overboard with it!

From the research ive done, the terminator system can command a pump on/off, but cannot modulate its duty cycle. Running a fuel pump at its maximum capacity 100%W of the time will work, but will also reduce its lifespan. A true PWM fuel controller will match the duty cycle of the pump with the demand. Just makes it a more efficient system. I would argue that any aftermarket fuel pump will benefit from a fuel controller. will it run without one, yes. Will if fail earlier, also yes.

To answer your question, my coupe is getting a forged LS3 based 416 with a focus on RPM. But when the 525lph pump is only $100 more than the 340lph, why not buy the insurance (or enable the addition of an LT4 blower later).

The LSAs in those ZL1's are quite the engine. 59 lb injectors with boost, so yeah, need a lot of fuel. I think you'll be perfectly happy with a NA LS3 416 in a car nearly half the weight!


This is where I got the idea you could use the Terminator X for fuel pump modulation: https://www.corral.net/threads/how-t...tor-x.2505786/

But honestly, my eyes glazed over halfway through reading



Good luck your build!

[PNWTim]

Whoa, what are planning that needs that big of fuel pump?

So, your question about fuel pump modulation opened a can of worms. I had never read in the forum of someone using a fuel pump speed controller. However, most builds on here have smaller pumps than you. I did some research and there does seem to be an ability for the Terminator X to act like a PWM, but the discussion went way over my head.

For my size fuel pump (340lph), it doesn't seem needed.




And Tim,

After reading more, I am going to switch over to the Terminator X handling the on/off of the Fuel pump, like you suggested. It's a safety thing. If the car crashes, the way I have it the fuel would keep pumping, perhaps spraying from broken lines onto hot headers and pipes.

My push button fuel pump switch is simply in the ground trigger loop for the relay. So I'll just hook up the Terminator X green wire to my push button and all will be well

Probably wise Jim. Your rollover module should also manage that situation if wired correctly but double safe is good. For what it's worth, the Terminator X probably has built in PWM control for your fuel pump if your pump is capable of supporting it. It's not particularly necessary but still a nice feature.

[JimStone]

No first start yet. I've been all ready to go for a week, but finding the right time when my family is all together and not rushing to/from sports games/practices or school events has been a challenge lately.



In the meantime, I've been messing around with some other things.


I posted this in the recent thread about Coupe LED taillights, but I'll post it here for posterity:




I've long been searching for LED halo taillights for the back of the coupe. I love that look and find the taillights sent with the kit to be very mediocre, at best.

GRP makes some really nice looking ones that have been used successfully by a few folks on this board. https://www.gregsraceparts.com/produ...print-3-eleven

My beef with the GRP halos are the large size that takes over the back of the car. Those are 4.75" diameter. I found some that are about an inch smaller, which doesn't sound like much but actually is 38% less surface area.

They are also $500 less than the GRPs



I found them at CarbonMiata.com, a retailer focused on custom parts for the Miata community.

https://www.carbonmiata.com/shop/hal...1105#attr=5147








I was skeptical of the quality at $70 apiece, but they seem to be legit. Supposedly hand made, but they don't look or feel DIY














They have integral lights in the middle that can be either back-up or turn signals.

The white LEDs that came with them were underwhelming, so I got replacements that are much brighter (not as noticeable in pics as in person). https://www.amazon.com/LASFIT-Upgrad..._rpt_ba_s_2_sc





There is also a function to use the actual ring LED as the turn signal, which I'm leaning towards

The halos are dual brightness (brake and driving lights). Both are very bright. The brakes are almost blindingly bright (a good thing). The driving lights are maybe a tad too bright, so I've ordered some resistors to see if I can take them down a little. Not a deal breaker if that doesn't work.

They come with LED drivers/wiring harnesses



I am going to ghost the center lens so it matches my blacked out theme

They have mounting studs so I'll figure out some way to mount them. Will need to be recessed slightly into th body. I don't know if I'll do the whole fiberglass "tub" thing that others have done. Probably will just cut a close fitting hole and make a thin bezel on Send-Cut-Send or my 3D printer.


You might tell I'm pretty excited about these. I think they're exactly what I was looking for.

[bishes]

I've been waiting for this post since you first announced that you'd ordered them, they look great! Can you share some details on why it took 3 months for them to arrive?

[JimStone]

I've been waiting for this post since you first announced that you'd ordered them, they look great! Can you share some details on why it took 3 months for them to arrive?

Dan,

I think I did get unlucky with the shipping and don't think 3 months is typical.

I expected it to take a while since they're "hand made" and coming from China. The first shipment took about 6 weeks, but inexplicably only contained the drivers/wiring harnesses. My contact at CarbonMiata, Marc (who manages the info@carbonmiata.com account) , was very apologetic and got another shipment going. I was following the tracking and noticed the 2nd package got held up at a Chinese package sorting facility for over a week. Marc was somehow able to get that sorted after I let him know.

The reviews from CarbonMiata are generally good and they do business globally. Marc was great about answering questions and sent me additional photos before I bought. I have a 24 email exchange with him.

I wouldn't let my experience scare you away. Just know it will take about 6 weeks to get them.

[bishes]

Thanks for the info, that's very helpful!

[Skuzzy]

Nice! It's always fun to read about others approach to making their car their own.

[jemorgan3]

Very cool taillights!

Was wondering how much clearance you gained with the LS2/C6 oil pan? It seems the best choice for ground clearance, but not so much for oil capacity.. Melling suggests at a minimum, a 6 quart pan when using the HV/HP pump, which my engine builder highly recommended for my bearing/ring tolerance. Is the LS2 pan above the frame? How much?

Thanks!!

[JimStone]

Very cool taillights!

Was wondering how much clearance you gained with the LS2/C6 oil pan? It seems the best choice for ground clearance, but not so much for oil capacity.. Melling suggests at a minimum, a 6 quart pan when using the HV/HP pump, which my engine builder highly recommended for my bearing/ring tolerance. Is the LS2 pan above the frame? How much?

Thanks!!

With the C6 pan, it is exactly flush with the bottom of the frame. My lowest point is the bell housing lip, which is about 1/2 inch below.










Improved Racing has a nice comparison page:

https://www.improvedracing.com/gm-ls...Jiiv6XZFwRuKxJ




Blueprint sends the engine with a 4th gen F-body pan



You can see it's 3/4" deeper than the C6






There may be something out there that has more oil capacity and still 4.85 in deep, but I couldn't find one that also would clear the rods on a stroked LS.


One alternative to a short pan would be to add spacers to the motor mounts to lift the engine up. I didn't want to mess with that

[460.465USMC]

Thumbs up on the tail lights, Jim. Saweeeet!

[JimStone]

Thumbs up on the tail lights, Jim. Saweeeet!

Thanks Chris!





One more thing regarding the taillights, then I'll put them away until body fitment time:

I was messing around with them today and figured out a way to easily make the center light recessed into the halo. That's something I really liked about the GRP Evora lights.




The center light can be detached by taking out the steel "pinch" triangle that locks (sorta) the center housing in place. Then it's just a press fit





Then rotate the triangular base to the next notch and use the pre-existing halo lens mounts, with longer screws, to secure the center housing. This keeps it perfectly centered









It's only maybe 1/2 inch, but I think will look great with a smoked center lens

[Skuzzy]

The recess does look better. Nice work.

[Papa]

I like the look of those!

[PNWTim]

I think it's the little details that really add up. Those are going to look great.

[JimStone]

Finally got around to doing the deed:




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A happy event. It almost didn't happen though. At first we got violent backfiring and roughness from the right cylinder bank. Eventually, we figured out the right coil harness was reversed. So it was basically trying to ignite on the exhaust stroke.

How did that happen? No idea. Clearly user error when reassembling the engine.

Thanks to my Dad and brother-in-law for helping me figure it out.

Thanks to my son for being standby firefighter. Fortunately, not needed.



Lewma will be proud - got that engine started!

[Higgybulin]

Great job man!! I was thinking the video was going to show the violent backfiring! You probably didnt want to see that again though!!
Congrats!!!!
Higgy

[Lugnut Mark]

Well all right congratulations….. now ……DO A BURNOUT …. sorry Jim I couldn’t resist….. btw the taillights look awesome !

[Papa]

Congratulations on the huge milestone!

[8secDuster]

Congratulations Jim !

[lewma]

Congrats Jim!!

[JTG]

Congrats Jim, that has to feel so good!!

[PNWTim]

Purrs like a kitten Jim. A little more throttle and the lion will appear. That's a great moment and you're fortunate to have the family in attendance.

[Jeff Kleiner]

Congratulations Jim! Big milestone

Is that you in the seat? Methinks your noggin is gonna' bump the roof!

Jeff

[cc2Arider]

Awesome moment Jim...and I agree, it is good to have your Family there to appreciate your milestone

Craig C

[460.465USMC]

Wahoo! Sounds mean! Congrats! I don't recall, are those Gas-N pipes?

[JimStone]

Thank you everyone for the comments!

Congratulations Jim! Big milestone

Is that you in the seat? Methinks your noggin is gonna' bump the roof!

Jeff

I fit in there when I test mounting the seats with the body on over a year ago... Maybe I grew? Might need to incorporate a Gurney Bubble

Wahoo! Sounds mean! Congrats! I don't recall, are those Gas-N pipes?

Those are FFR pipes that I Cerakoted

[AaronR]

Wow, your engine sounds like it's running great. That's a beautiful purr! I think we have the same engine. I also got the BP 427 LS engine for mine. Good to know I will need the C6 oil pan. I'll just go ahead and buy that now which will make the 3rd oil pan I bought for this... ha. What windage tray and pickup tube did you use for yours? Were you able to reuse from the pan supplied by FFR?

I'll be using an 8HP75 transmission with mine instead of the T56. I just picked that up last week. Hopefully I won't have any clearance issues with the bellhousing since it's rather large on the Ram version I have (it's from a 2024 Ram 1500 2wd).

I'm really enjoying seeing your progress and hopefully learning from some of the hard-earned experience you're sharing. Thanks!