Camera's 818C [Archive] - Page 3 - Factory Five Forums

mcamera

09-02-2022, 01:49 PM

Sealing that long, thin gap under my firewall made a huge difference! More than I expected. There's less engine noise in the cabin now and the tone is nicely muffled. The car is becoming more refined. The 1/4" gap was between the silver and black firewall in the pic below. The seal I added is along the bottom of the black firewall, in between the 2 firewalls.

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I've wrapped a couple more console panels. I had 2 holes I wanted to fill so I used a little spackle and sanded them smooth which worked well. The interior is coming together with the carpet I cut for the foot wells. I've ordered another sheet of leather wrap to do the center of the console. The remaining panels will wait until winter when I take the seats out. I'm enjoying driving the car while the weather is nice :)

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I've been searching for cup holders and debating how I want to add them. I narrowed it down to these 2 styles. Both types will fit if I mount them in the center of my console in front of my shifter (for depth requirements to avoid the frame tubes). I can do 1 big cup holder that looks too big in my opinion or squeeze 2 small cup holders in a line. I've ordered the 2 small holders and will see if that works out. In the pics, the red ring is the lip of the cup holder that stays on top of the center console and the gray circle is the portion that will stick down into the console.

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mcamera

09-08-2022, 11:09 AM

Email me at mikejcamera@gmail.com if interested

Short Shifter
$20 (retail is $50)
93+ MR2 shift lever (standard on Zero Decibel Motorsports shifter)
https://primemr2.com/products/mr2-shift-lever-93

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Short Shifter for Factory Five plastic shifter
$40 (retail is $115)
2.5" height reduction / 35% throw reduction
https://www.torquesolution.com/product-p/ts-ss-019.htm

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Pressure Control Solenoid Valve
$50 (retail is $215)
From 2007 WRX
Fits many 2005-2008 vehicles including Forestor, Impreza, STI, WRX (see link for complete list of compatible vehicles)
https://parts.subaru.com/p/Subaru_2007_WRX-25L-TURBO-5MT-4WD-SEDAN/Valve-Pressure-Control/49250205/42084AE130.html

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Charcoal Canister Solenoid
$20

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mcamera

09-08-2022, 12:23 PM

Driver Wiper
$20 (retail is $65)
Brand new, opened but never installed
Fits most 2004-2007 Impreza, WRX, and STI (check link for full list of vehicle compatibility)
https://parts.subaru.com/p/subaru__/Windshield-Wiper-Arm-Wiper-Arm-DriverWindshield-Wiper-Arm/49299787/86532FE100.html

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mcamera

09-14-2022, 10:28 AM

I finally turned off the last remaining light on my dash, the parking brake light. I couldn't figure out this weird "reverse circuit".

I had power at C7, but didn't know what do with B19.

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Then I found another diagram in the ABS section. It shows a light blue (Sb) wire completing the parking brake light circuit. I grounded that and my light finally turned off! I spliced it into the black w/ white stripe (BW) ground wire from the same connector to ground it permanently.

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I still don't fully understand how this works. It looks like the reverse circuit keeps the light on when the circuit isn't grounded, and then turns the light off when it is grounded. But the reverse circuit has it's own constant ground? If anybody can explain it, I'd like to understand it better.

On another note, I noticed that my car was sitting really crooked. The passenger side looked low. So I measured around the car and found that the front passenger fender was 3/4" lower and the rear passenger fender was 1/2" lower. A large difference.

Ground to fender measurements:
FR 24-3/16"
FL 24-15/16"

RR 25-8/16"
RL 26"

Ground to frame measurements:
FR 4-5/16" (want 4.5" clearance, so this confirmed FR is low, instead of FL being high)
FL 4-9/16"

RR 4-3/16" (want 4.5" clearance, so this confirmed RR is low, instead of RL being high)
RL 4-6/16"

To get the body level I wanted the FR fender up 12/16", so I adjusted the FR spring up half of that (6/16") since it's closer to the LCA pivot point which worked well. I wanted the RR fender up 8/16", so I adjusted the RR spring up half of that (4/16").

The body is significantly more level now. After raising the passenger side though, my driver front fender also went up quite a bit. I have to lower the driver fender a 1/2" tonight. I confirmed the frame is at 4.75" on that corner now, so I want to lower the frame back to 4.5".

mcamera

09-14-2022, 02:22 PM

My interior is coming together. I figured out a way to add a simple bluetooth radio for $50. There's no head unit so everything is hidden in the car. Part links and sound clip are below.

It's a bluetooth amp + 2 speakers. This setup can get really loud, but there isn't much bass due to the small 4" speakers. I only have them turned up about 1/3 of the way but might look at bigger speakers to improve the bass/sound quality now that I know I have space. I mounted the amp in my center console and tapped into the front accessory plug of the Subaru wiring harness for switched power (in pic below, Pin 1 = switched power / Pin 2 = ground). So the amp turns on/off with the key and doesn't drain my battery. It also connects automatically to my phone when I start the car. This model of amp has a chime for power and connecting to bluetooth but no foreign voice like a lot of the other cheap amps.
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Sound Clip

https://youtube.com/clip/UgkxBnzqUe-TKXFw4vbwpVW9j_G8sAW4OMDe

I bought a generic Corolla shift boot and cut it shorter to work in my console. Actually a nice quality leather for $10. I also had just enough room for 2 small cup holders. My interior is getting a lot more comfy.

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$19 Bluetooth Amp
https://www.amazon.com/dp/B07XBF9GXW?...

$27 Pioneer Speakers
https://www.amazon.com/dp/B00G9T0RJU?...

Leather Vinyl Wrap
https://www.amazon.com/dp/B083JMG9CL?...

Cup Holders
https://www.amazon.com/dp/B075TSXHTJ?...

Shifter Boot
https://www.amazon.com/dp/B07S68934W?...

RPGs818SNA

09-14-2022, 11:17 PM

I still don't fully understand how this works. It looks like the reverse circuit keeps the light on when the circuit isn't grounded, and then turns the light off when it is grounded. But the reverse circuit has it's own constant ground? If anybody can explain it, I'd like to understand it better.

The "reverse circuit" works exactly as you describe. They use transistors to implement the function of course, but here's a crude relay version as an illustration.

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When the sensor wire is open, the relay is closed and the lamp lights with all 12 volts across it, except the 0.7 volts across the diode. When the sensor wire goes to ground, the 0.7 volts across the coil opens the relay and the lamp goes out. We have to assume the coil is sensitive enough to activate with 0.7 volts and has enough resistance to keep the current through it low enough so the lamp doesn't light. Such a relay may not exist, but you get the idea.

Thanks for sharing so many useful tips along your build journey.

RPG

mcamera

09-15-2022, 09:47 AM

Thanks for the explanation RPG! That makes sense now. Your diagram is better than a box that just says "reverse circuit".

mcamera

09-21-2022, 01:21 PM

Those 4" speakers did not impress me after a week. They played clearly but had no bass or depth to the sound. I bumped up to bigger, better, and somehow cheaper 6.5" speakers. Just one of those things where bigger is better. Here's a 1 minute comparison on my channel.

https://youtu.be/KcKYhWL2mmo

JVC 6.5" Speakers
https://a.co/d/e0VFQ5U

Made some simple aluminum brackets. The passenger side brackets are beefier 1/8" aluminum since I only mounted 2 points. The last pic shows how much clearance I still have with the dash on.

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mikeb75

09-25-2022, 09:45 AM

For the gaps between the quarter-window and the rear bulkhead/firewall I wrapped a piece of balsa wood with excess headliner material, then I installed it in the hardtop in the black stripe of the window glass. Unfortunately, this is the best picture I have available of it:
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It makes a significant difference in both noise and heat when added to the FFR supplied rubber trim for sealing the engine bay.

mcamera

11-07-2022, 11:00 AM

mcamera

11-07-2022, 11:03 AM

My 818 started to break up under full throttle a few weeks ago and I thought it might be a vacuum leak. So I also made a video on how to use a smoker to test for leaks.

https://youtu.be/4Zp0gVZaJMw

FFRWRX

11-07-2022, 12:37 PM

I put out a video last month showing how much my 818 cost to build over the last 2 years. I show all my costs and break them down into these categories: required, recommended, wanted, and not needed/applicable for every build. It's always fun to see what people think is worth their money. Enjoy!

That is excellent! Some people don't want to know how much they end up spending, or fool themselves into believing it it less than they actually spent. If you keep track of all the smaller items it can really add up.

Your cost for a very nice build is very realistic. Those that have a quick view of You tube videos (posted by people using the basic kit cost and nothing else, who have never built a car in their lives) think they can do it for $20k or less. My build isn't finished yet, but close. So I know what it will cost when completed. Converting Canadian $$ (where I am) to US $$, I am pretty close to where you are on cost. That is assuming I started from scratch, but I bought mine off someone else who started it and I did save a lot doing that.

And as for "what people think is worth their money", that is a funny one. I will make things myself to save a few $$ and then spend hundreds on something I could have made. Usually I'll make something that I think I can do better than what is available, or can't get the part quickly, or just for the fun/challenge of it. Defies logic at times.

Rick
ps. And thank you for posting. This part of the forum is dead these days.

Dave 53

11-07-2022, 02:15 PM

Put me in the camp of not wanting to know what I've spend on my 818S. What I can say is turning it from a street car into a proper track car has added at least $5,000 and still going. I'm the process of installing a $800 LSD that isn't needed on the street but is a must have on track. The OMP Style seats look good and are very comfortable driving to the track, but they're marginal in long sweeping 1.3g turns. Just sent an email last night to someone local selling a properly supportive track car seat on Craigslist for $500. While I have a portable fire extinguisher, high on the to do list is a proper fire suppression system for about $500. It's a working track car, not a show car, so the scratched-up Gel Coat is fine - no need for paint or a wrap, so at least that saves several thousands of dollars. Could I have gotten a track prepped production car like an S2000 or M3 for less? Probably, but it's not the same in a way I can describe.

mcamera

11-08-2022, 10:20 AM

That is excellent! Some people don't want to know how much they end up spending, or fool themselves into believing it it less than they actually spent. If you keep track of all the smaller items it can really add up.

Your cost for a very nice build is very realistic. Those that have a quick view of You tube videos (posted by people using the basic kit cost and nothing else, who have never built a car in their lives) think they can do it for $20k or less. My build isn't finished yet, but close. So I know what it will cost when completed. Converting Canadian $$ (where I am) to US $$, I am pretty close to where you are on cost. That is assuming I started from scratch, but I bought mine off someone else who started it and I did save a lot doing that.

And as for "what people think is worth their money", that is a funny one. I will make things myself to save a few $$ and then spend hundreds on something I could have made. Usually I'll make something that I think I can do better than what is available, or can't get the part quickly, or just for the fun/challenge of it. Defies logic at times.

Rick
ps. And thank you for posting. This part of the forum is dead these days.

Thanks Rick! I spent more than I planned but a lot of items came down to convenience and trying to keep yourself from doing it again a year later. I put $1000 into the water pump, timing belt, spark plugs, and reinforced oil pickup while the engine was out and easy to work on. But sure enough, 4 months after driving one of my ignition coils dies. I had them out to do the plugs early in my build, but didn't want to spend the extra $400 at the time. Not a big deal, but some items you only get to choose pay now or pay later.

It would be hard to build a car for $20k. You'd have to cut so many corners. Lots of compromises and I think you'd have to ignore maintenance.

I would have liked to do more custom projects for the car in certain areas, but I was afraid I would never finish the car if I stopped for every idea. I kept my focus on fully finishing "a car" and not trying to build "half of a dream car". I'm so happy I got to drive it around for a summer with less than 2 years of building.

Put me in the camp of not wanting to know what I've spend on my 818S. What I can say is turning it from a street car into a proper track car has added at least $5,000 and still going. I'm the process of installing a $800 LSD that isn't needed on the street but is a must have on track. The OMP Style seats look good and are very comfortable driving to the track, but they're marginal in long sweeping 1.3g turns. Just sent an email last night to someone local selling a properly supportive track car seat on Craigslist for $500. While I have a portable fire extinguisher, high on the to do list is a proper fire suppression system for about $500. It's a working track car, not a show car, so the scratched-up Gel Coat is fine - no need for paint or a wrap, so at least that saves several thousands of dollars. Could I have gotten a track prepped production car like an S2000 or M3 for less? Probably, but it's not the same in a way I can describe.

Reading through the build threads years ago, showed me how difficult/expensive it was to make these into track cars. It would be rewarding and a lot of fun but it was beyond the scope of my project/budget. These cars are really capable though so I hope once you get everything setup you have a blast out on the track! Agreed, you can buy a production car whenever you want. Have fun with your unique 818 as long as you enjoy it.

mcamera

11-23-2022, 08:16 AM

Trying to solve my misfire issue under full throttle

https://www.youtube.com/watch?v=t3Z2AUCD19o

mcamera

11-23-2022, 08:18 AM

Monthly video update

https://www.youtube.com/watch?v=uQ3h5q0WozU

mcamera

11-23-2022, 08:19 AM

Bench test to see how well my sound insulation works

https://www.youtube.com/watch?v=jsAhCbAozUc

mcamera

12-05-2022, 11:22 AM

I still see some 50 deg days in my weather forecast but I think my driving season is finally over. We're expecting a lot of rain and half way through December the temps can't stay this high for much longer in Kentucky. My wife's 69 Mustang is going into storage so I'll finally have room to work in my garage again. I have a laundry list of winter build items to do, but I want to do a few extra fun bits. I'm just not sure what yet. Is there anything you've done to your car that really impressed you or just made it more enjoyable?

Examples

- I have upgraded engine mounts because I really enjoyed the sharper steering and gas/brake inputs from a previous Acura RSX I had upgraded
- I have lightweight seats, wheels, and an aluminum gas tank for functional weight reduction to make the car more agile
- I have larger 8.5" wide rear wheels because that was the biggest I could fit with the stock trail arms for max grip

A few items I can think of that may be a fun upgrade:

- I'm strongly considering getting the car corner weighted in the spring. The handling is sharp and quick, but the front tires feel like they're a little on edge. I think my steering could inspire more confidence.
- The car likes to spin 1 wheel because it has an open diff. Not sure how difficult this is to install but would I even see an improvement on a street car? I think yes, but I have no experience in this area.
- Stiffer springs to reduce body roll (no current issues, but maybe it could be better?)
- 3 port boost controller / turbo upgrade / intercooler upgrade (I'm reluctant to go down this slippery slope and need bigger injectors, start stripping gears, need another tune, etc)
- Engine bay lighting

Ajzride

12-05-2022, 11:51 AM

I didn't look back through your whole build thread, but if you have not done a duct to get the radiator heat flowing through the hood vents, that will make a mountain of difference in the summer.

Dave 53

12-05-2022, 06:42 PM

It's a slippery slope going from a streetcar towards the direction of a track car trying to improve an already competent car. In general, I try to make car improvements in the order of safety, reliability then speed. And speed / fun comes from skill, braking, handling, then horsepower in that order. Some may have a different order, but I'd argue skill needs to be high on the list. I see a lot of lack of skill YouTube fail videos.

If the front end feels "a little on edge" and you haven't installed a bump steer kit, for sure do that next.

Of your short list above, an LSD might be a worthwhile improvement if you're feel one wheel spinning. I just did it. It wasn't as scary of a job as I thought it would be. DSR-3 has one for sale.

A day or two at some sort of performance driving school would most likely do more than hardware improvements. A few lessons and some practice on throttle steering and threshold braking will serve anyone far better than more horsepower. A friend tells me throttle steering around a 270 freeway off ramp can be a lot of fun. Without ABS and adjustable brake bias, knowing how to adjust the bias and having skill (through practice) in threshold braking is a safety necessity. I'd put learning to drive the car you have in the "safety" category.

Spend some money on a helmet and an autocross event before chasing horsepower.

mcamera

12-06-2022, 02:16 PM

Ajzride,
That's a cool idea. I've seen people put a baffle above the radiator to force more air through the radiator but haven't seen ducting after the radiator. Have you had temp issues? I drove my car on the street all summer (up to 95F outside) and never got the temp gauge past half. Even in stop and go traffic.

Dave 53,
Yeah I've never been one to chase high power. I prefer simple and reliable.

I have a bumpsteer kit that helped but it could be better. I lost a degree of caster on my 2nd alignment and it shows. I get some minor bumpsteer over big bumps. That's why I'm interested in getting the car corner weighted/a more advanced alignment. I think I could refine the handling and gain traction all around with that one change.

I agree with ya. I've done a couple track days and autocross in other cars and it taught me a lot. Slightly concerned about the Subaru boogey man (losing oil pressure) while tracking the car though. I feel like I have to do an event though to figure out the car like you're saying.

mcamera

12-06-2022, 02:17 PM

https://youtu.be/eBfVoe41_Aw

Ajzride

12-06-2022, 02:36 PM

The duct I’m talking about is to exhaust the hot air exiting the radiator out over the windshield and keep it from heating up the cabin.

mcamera

12-08-2022, 09:41 AM

The duct I’m talking about is to exhaust the hot air exiting the radiator out over the windshield and keep it from heating up the cabin.

Ah! Makes sense.

mcamera

12-13-2022, 11:32 AM

https://youtu.be/HiadFOpdb58

FFRWRX

12-13-2022, 04:32 PM

Another excellent video! I think the weight is very good. I never expect a F5 car to weigh what they say it does. My first Cobra from them certainly didn't. So it is like a Subaru with 1000 lbs taken off it......not bad!

Rick

lance corsi

12-13-2022, 07:09 PM

I’d say your car’s weight is pretty typical of 818 coupes. I’m hoping to come in at less than 2200 lbs.

Shawn818c

12-13-2022, 09:28 PM

I can get you the weight of the factory subaru mirrors with FFR brackets if you'd like! I have them sitting on a shelf, like Wayne said you won't want them for the coupe. They're useless.

**edit** Sorry, I mean mirrors but I can get you the weight of the Subaru wiper system too if you would like.

mcamera

12-14-2022, 10:42 AM

Up until now, I've been telling people the car weighed 2000lbs and I believed that. So it doesn't change how well the car drives. It's still as quick and nimble as I wanted, but I'm slightly disappointed I couldn't stay under 2000lbs. I didn't add any big items like heat/AC. I kept the small Subaru brakes. Chose modest wheel sizes (8.5" rears). Replaced some big Subaru parts with smaller options (charcoal canister, handbrake, air intake, mirrors). Overall I saved weight compared to a standard build. I still don't think the hardtop, window motors, and 6 pieces of glass added 300lbs compared to the convertible body panels in the rear.

I wonder if my 07' EJ255 weighs any more than the 02-05 EJ205?

Bob_n_Cincy

12-14-2022, 01:27 PM

mcamera

12-29-2022, 01:33 PM

https://youtu.be/bIo34K1WWIw

mcamera

01-10-2023, 10:26 AM

https://youtu.be/Miqbt6o6y5g

lance corsi

01-10-2023, 06:56 PM

Mcamera, in order to fix your rear hatch alignment, raise the hinge points closer to the roof. This plays an important part in the dynamics of the hatch hinge design. You can only go as high as the roof will allow.

mcamera

01-11-2023, 09:29 AM

Thanks for the suggestion Lance. I just checked and my hinge point is as high as it can go before the arm interferes with the roof. My hatch opens well, it just settled over a few months and started to rub at the bottom. Likely from the struts always pushing on it. Hope your build is going well.

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lance corsi

01-11-2023, 01:20 PM

Yea, it’s going and going and going….

BigDanSubaru

01-15-2023, 08:59 PM

[QUOTE=mcamera;443367]The fuel fittings I ordered work great. They fit underneath the firewall and installed easily. My driver side firewall hits the fuel inlet on my Boyd tank before it can reach its final position though. I'll have to bend the horizontal section of the firewall or shim the bottom up about an inch to clear that.

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The fuel filter bracket I took a gamble on is perfect. The mounting holes are the exact same spacing as the old mounting holes for the AC compressor. I just need to drill out the mounting bracket holes a little bit, and buy 2 shorter bolts. This makes good use of dead space on the engine (where the AC compressor used to be) and I don't have to mess with mounting the filter to the frame rail and through my rear-rear firewall as the manual recommends. Here's the part number and a link if anybody wants a cheap and easy fuel filter setup using an 02-04 WRX filter. I had to switch over since my 07 filter was mounted in the fuel tank and now I need an externally mounted filter.

$19 - Canton Racing Filter Mounting Bracket - Part# 26-893 (https://www.summitracing.com/parts/CTR-26-893)

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I have an 07 WRX donor and I am running the Boyd tank just like yours. I bought all the same fittings and the 02-04 fuel filter with the Summit bracket too. (Excuse me for copying your homework). I am curious about what you ended up doing with some other components of your fuel system.

1. Did you retain the 07 WRX OEM fuel pump control unit and factory wiring?
2. Did you retain the OEM fuel pressure regulator? Where even is this on the 07 WRX?
3. Did you retain the inline fuel damper things that were on the fuel supply and return lines right before they attach to the hard lines on top of the intake manifold?

I have seen some builders mention that the Aeromotive 340 pump draws more power than the OEM unit and I don't want a fire or anything. I have also seen some use an aftermarket fuel pressure regulator, but I don't really want to spend an extra 200 or more dollars on something that isn't necessary. How is yours running? Any starvation issues or anything? Sorry for all the questions. I just want to make sure I am taking care of these things as I go so I can avoid having to undo work later.

Also, keep up the videos on your interior work for YouTube. Good stuff!

Dave 53

01-15-2023, 09:50 PM

I'd suggest using high pressure fuel injection hose in the fuel system and not heater hose.

mcamera

01-16-2023, 08:54 AM

Hi Dan,
I put that info on here to hopefully save somebody time and money. Glad you're getting some use out of it!

1. Did you retain the 07 WRX OEM fuel pump control unit and factory wiring? Yes

2. Did you retain the OEM fuel pressure regulator? Where even is this on the 07 WRX? Yes, see pic below for location

3. Did you retain the inline fuel damper things that were on the fuel supply and return lines right before they attach to the hard lines on top of the intake manifold? I don't remember removing any dampers but there's nothing on my lines now. See pic below. Just a line in from the filter, and line out to the tank.

I've had no issues and my tuner wasn't maxing anything out. I'm still using the stock turbo, just turned up from 11.5psi (stock) to 16psi (current tune). I go over my dyno numbers including A/F ratio in this video if you want more details: https://youtu.be/ile68VJnZCk. He had no problem holding A/F numbers.

Thanks! Most of my interior materials are on backorder but I have some coming in today. Been working on other 818 things all weekend though!

Dave,
Early in my build I grabbed the wrong hose (heater hose) but I am running the correct fuel hose. Doesn't hurt to double check and I just did. Thanks for the note!

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mcamera

01-30-2023, 08:31 AM

https://youtu.be/3iDgBMeu3D0

Not a pro by any means but here are some of my tips for anybody that isn't familiar with vinyl wrapping.

RPGs818SNA

01-31-2023, 09:38 AM

Thanks so much for sharing your experience with vinyl wrap, especially the video. I decided to try it on my firewall and tunnel cover too. I got a 5x5 and a 5x2 sheet which was enough for all the firewall and tunnel pieces. My first application was the rear tunnel cover for practice. I only used 1 inch borders, so lining the vinyl up with the piece with just the right overlap was tricky. Later I taped cardboard pieces with a 1 inch overhang to the bottoms, making it much easier to line it up.

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I found the application was pretty easy, given all the surfaces are flat. I wrapped teeshirt fabric around a credit card to smooth the vinyl on. I found that heat did indeed shrink out any stretch marks, but it also tended to make the vinyl brittle, so I used it sparingly. Once in place, it needs to be heated above 90 degrees to set the glue. However, that does tend to pull the vinyl away from the inside corners.

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It looks and feels great, is tough against scratches and doesn’t move under a tightening screw head. It does attract dust, so it could use an antistatic treatment. I’m pretty happy with the result.
RPG

mcamera

01-31-2023, 01:17 PM

Looking good RPG! Did you also use the leather textured wrap? I cut my pieces a few inches too big to make placement easier, and then cut the excess down to 1" later. I have everything finished just waiting for my carpet to be delivered. It was on backorder for 2 weeks, and now it's another 4 weeks so I cancelled and bought from somewhere else.

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RPGs818SNA

01-31-2023, 03:24 PM

Thanks. I used the wrap you were so kind to link to in your post #498. Good stuff. Your firewall looks perfect! Nice work.

I'm trying to get all the pieces on the vinyl I have, so 1 inch borders. :) I'm also keeping the passenger side of the tunnel straight, so no need for the skirt that extends over the 2x5 piece.

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Thanks for pioneering the vinyl wrap. I look forward to your carpet posts.

RPG

mcamera

01-31-2023, 04:21 PM

Looks like you're using every bit of wrap! I kept my passenger side tunnel straight also. Much simpler and gives some extra foot space.

mcamera

02-24-2023, 08:50 AM

https://youtu.be/UlCdqDKlYg8

I visited another builder in Kentucky to answer some questions on his 818R and 818C builds. He has a lot of projects going on in that garage. I can't wait to see how they turn out.

mcamera

03-07-2023, 02:15 PM

https://youtu.be/CzsFh9JDl2o

Dave 53

03-08-2023, 12:12 PM

FFRWRX

03-08-2023, 12:58 PM

Another very good video and a nice interior. I like the mesh in the front grill and may have to look into that.

mcamera

03-11-2023, 09:18 AM

Instead of painting the wheel well splash guards, maybe consider using your spray glue and Walmart yoga mat. I added a few rivets with washers in areas that looked like it might peel back. It also makes for a cleaner look because you can form fit the yoga mat instead of using the rubber bulb weather stripping181285.

That does look good Dave! I actually don't get many annoying noises from my front fender wells like some people complain about but removing the bulb looks nice.

Another very good video and a nice interior. I like the mesh in the front grill and may have to look into that.

Thanks I appreciate that! Having the bottom opening on the front grill always looked unfinished to me with that skinny fiberglass lip.

FFRWRX

03-13-2023, 05:19 PM

Thanks I appreciate that! Having the bottom opening on the front grill always looked unfinished to me with that skinny fiberglass lip.

Is it plastic? I like the hex shape.

mcamera

03-14-2023, 10:13 AM

Yep ABS plastic

https://a.co/d/j5SoSfH

mcamera

06-11-2023, 04:17 PM

https://youtu.be/5KjGpUX1Xu0

Jetfuel

06-11-2023, 06:21 PM

You learned something new and had fun doing it.
Win. Win..

Jet

mcamera

07-07-2023, 11:06 AM

https://youtu.be/4bxTs8ic5XE

STiPWRD

07-07-2023, 03:48 PM

lance corsi

07-07-2023, 03:54 PM

Thanks for the videos!

mcamera

07-07-2023, 04:27 PM

Glad to see your axles survived the drag strip, I could tell you were taking it easy on the launch. I thought you had the car tuned from one of your earlier posts, the boost creep didn't show up then?

Yeah I didn't want to grenade my trans or axles. Didn't realize how sticky dragstrips are. I see how people break things now. I have a stock EJ25 that's tuned to about 276hp/300tq. Creep has never showed up but this is the first time I've run the car through 4 gears at full throttle. By the end of 4th the gasses must get hot enough/have enough volume to overwhelm the wastegate. From my searches it looks like a common issue for this engine. Most people said the same thing about never having an issue until the top of 4th gear.

mcamera

07-21-2023, 01:15 PM

https://youtu.be/C8hy2xtUSew

More helpful for somebody who hasn't built this car yet and is wondering how difficult maintenance is on a finished car

FFRWRX

07-22-2023, 03:58 PM

I had my first on road failure. While I was flooring it the car made a loud sound and stopped accelerating. I changed gears and the car wouldn't do much, so I immediately thought the trans had failed. I pulled over and realized my coupler had pushed off my throttle body while under boost. It didn't help that my intercooler is mounted on the passenger side, but the driver side mount isn't attached to anything. So the intercooler was able to rock backwards and let the coupler push off. I tightened the coupler with a pocket ruler I had in my work backpack and limped home.

This is kind of funny (it wasn't at the time though). I read this post when you first wrote it, and commented that I hadn't secured my IC at all. So I bolted down the passenger side and that seemed pretty good. I went for a short drive yesterday (car not road-legal yet) and was pleasantly surprised how nicely it drove. Decided to "give it the beans" in 2nd gear and there was this great rush of air and no power at all. Managed to limp home. Yup, the IC had pivoted back on the one side that was bolted down and the coupling tube came off. So this morning was spent making a bracket for the driver side.

my turbo jacket installed. Trickier than expected. Had to fish some wire around the turbo so I could get the springs pulled through and attached. Looks nice, matches my DEI wrap really well, and the wool on the inside leaves lots of fiberglass-like pokies in your hands.

Are you happy with that blanket? The other thing I noticed on my short drive is how stinking hot the turbo gets. And mine is pretty close to the trunk. I was going to order one but looking at the space around the turbo I didn't want to order something that wouldn't fit.

Thank you again for your tips and fixes.

Rick

mcamera

07-24-2023, 11:07 AM

That is funny. Scary in the moment but luckily an easy fix. I also realized the previous owner had used a plumbing coupler on my intercooler instead of an automotive coupler. It was hard deformed plastic that I replaced with a silicone coupler lol.

I really like my Mishimoto turbo blanket. Modestly priced at $100 shipped. I wanted a "fitted" jacket because I thought it would look better but this one looks great and has held up well. I don't think the turbo blanket helps as much as the exhaust wrap until you start tracking the car. The exhaust has so much surface area I think it throws off more heat. Wrapping both definitely helped though.

Here's the blanket I bought. Fits the stock turbo.
https://www.mishimoto.com/subaru-wrx-sti-titanium-turbo-blanket-2001-2017.html

DEI exhaust wrap and zip ties that I bought. Matches the Mishimoto jacket really well. I bought 15ft and it was tricky to cover my stock downpipe w/ cat and the FFR angled pipe off the turbo. Barely enough.
https://www.summitracing.com/parts/DEI-010129
https://www.summitracing.com/parts/SUM-350129

FFRWRX

07-24-2023, 12:07 PM

Thank you very much. I have wrapped parts of my exhaust, where it is close to adjacent parts, and put a heat shield under the trunk. I don't expect miracles from the turbo blanket, but everything helps. I ordered the blanket.

I was also thinking of putting a small ducted fan on each air inlet pipe that comes from the roof scoop. The small ones that boats use for engine compartment ventilation. I've used them previously for Cobra footbox cooling.

mcamera

07-26-2023, 09:32 AM

https://youtu.be/7LNB5tEA9oE

FFRWRX

07-26-2023, 12:22 PM

A real pain to get at that, but glad you found it and sorted it out. But...............20 volts?

mcamera

07-26-2023, 01:01 PM

You saw it. 20 volts at 3 of the 4 wires attached to the fuel relay. Must get stepped up somewhere. The fuel pump probably draws quite a bit of constant power.

RPGs818SNA

07-26-2023, 03:56 PM

I saw 20v, but am skeptical. You might want to check your battery voltage on the 600V DC setting and again on the 20V DC setting. I suspect the meter is mis-calibrated on the higher range.

Seeing how much effort you put into getting to your fuel pump, I hope mine never gives out. Thanks for the videos.

RPG

FFRWRX

07-26-2023, 04:50 PM

I thought the same thing. I think I've read that the control may step down the pump voltage under certain conditions, but increase it? I'm skeptical as well.

Mark Eaton

07-26-2023, 10:04 PM

Wow, not sure what to think. I used a ton of those type solder connections in my wiring harness... which crimp connectors and crimp pliers are you using?

Rob T

07-27-2023, 05:39 AM

I had an intermittent fuel pump failure on my R. Sometimes the fuel pump would power up when power was applied, other times not. My issue ended up being the variable speed fuel pump controller. Because my car is used exclusively at the track, mostly at high engine loads, I did not replace the expensive variable speed controller, and simply installed a switched relay to the fuel pump, which now runs all the time, when power is supplied. The advantage of the switched relay for me, is that it allows me to crank the car (at starter motor speed) to build oil pressure before I let the engine run. This is useful for me because my car sits for weeks at a time between track days. I hope yours was the connection, and that the problems are behind you. There is nothing more frustrating than a car not starting when you expect it to....It's especially frustrating when you've paid $300 for a track day and your car won't start....

mcamera

07-27-2023, 07:50 AM

Measured my battery on 3 DC settings and the 600v setting is a few volts off. Not a problem when I was testing the relay for power (it was going to be yes or no) but it is slightly inaccurate for measuring lower voltages. Funny enough, it still only read 15v at the battery where my fuel relay was seeing 20-21v. FYI my fuel system is stock except for the Boyd fuel tank + Aeromotive Stealth 340 pump it comes with. Maybe my tuner changed some fueling settings that increased pressure/draw?

600v
187850

200v
187854

20v
187853

I'm using a pair of electrical pliers I bought from Home Depot a decade ago. I bought the crimp connectors at AutoZone. I used solder seals across my entire car and I've had a driver window issue, this fuel pump issue, and my car occasionally won't crank (until I push around some wires underneath the dash and play with the clutch switch... I think it may be the clutch switch sticking... once the car is running it has no issues). Rob, I almost missed my autocross heat last weekend because my car wouldn't start. It was only $65 but I feel your pain!

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Mark Eaton

07-27-2023, 10:09 PM

Did you check for continuity across those solder connections you cut out?

mcamera

07-28-2023, 06:28 AM

I essentially did that in the video where I moved the fuel pump wires and then the pump got power. Moved the wires again and the pump had no power. Moved the wires again and the pump got power. But, I dug the old solder seals out of my garbage and did a continuity test for science! They are showing the wires are connected. However, I haven't had the fuel pump falter even once since I replaced the solder seals 6 weeks ago. Including my autocross last weekend where everything got a good shake down. I'm confident the solder seals were the source of my fuel pump issue.

187903

Ajzride

07-28-2023, 07:56 AM

Hard to argue with the evidence, but the just doesn't make any sense. When you used the solder seal, did you twist the wires together before sliding the sleeve over and heating, or did you just slide the wires inside the sleeve and heat?

RPGs818SNA

07-28-2023, 08:51 AM

Continuity tests with a multimeter typically use between a microamp and a milliamp to measure resistance. Any bare metal contact at all between the wires will give a low resistance reading. If the contact area is tiny, a fuel pump pulling 5 amps will overheat that tiny area causing it to oxidize around the edges until there is no more bare metal contact, and no more current flow. Wiggling the connection can cause the wires to abrade the oxidation and touch again for a while. A good crimp makes the wires touch in a large enough air tight area to prevent heating and oxidation. A good solder joint will do the same.

mcamera

07-28-2023, 09:04 AM

I just stuck the wires in and heated the sleeve. The connection worked flawlessly for 2 years so there was a good, solid connection. The sleeve has a glue inside of it that holds the wires in place and I've confirmed the wires have not been pulled out any. So the only reasonable explanation is that something changed where the solder is connecting the 2 wires. The solder has cracked, crumbled, oxidized, corroded, something.

I gently cut open a solder seal and sure enough, the solder has cracked and separated. I thought the solder would have penetrated the wiring a little better but you can see a lot of copper on the black wire.

187905 187904

Twisting the wires together before you seal them would be better, but you'll still be relying on crumbling solder to a degree. I wouldn't recommend it. Several people have told me these get brittle and stop working after a couple years and now I agree. I will only use crimp connectors from now on.

I also remember Wayne from Very Cool Parts recommending crimps over solder in an old thread. He's built plenty of cars, tracks them, and is a professional mechanic. I think that says something.

187906

Case closed.

FFRWRX

07-28-2023, 11:20 AM

I've never used them, but it seems to me that it is a compromise design. Solder generally melts at a much higher temperature than it takes to heat-shrink a sleeve. I wonder if they use a low temperature melting solder and a high temperature heat shrink? You are trying to melt solder through heat shrink sleeve. I've never had an issue with soldered connections with a heat shrink sleeve applied after soldering. I use crimps as well, with a crimping tool like you use. Everything I've read says to never use one of those, use a proper ratcheting crimp tool. Someday I should get one.

Ajzride

07-28-2023, 01:03 PM

Bicyclops

07-28-2023, 03:35 PM

It is a very low temperature solder, I would not be surprised if the heat introduced by the amperage of a fuel pump would compromise it.

I do use the solder sleeves, but I always twist them really good and fold them back on themselves before I put the sleeve on, and I'm basically only using the solder to help keep the twist/fold tight. I definitely see how just sliding them in and heating them would be problematic. To be fair, that is how they advertise them, but I never trusted that method. I prefer to use double crimp connections for all of my connectors (see link below), but they don't make a splice using those, so I have stuck to the solder sleeves around tightly twisted and folded wires. When you do it that way, you have to go one size up on the solder sleeve, so it's not a slim solution.

https://www.amazon.com/gp/product/B0978S514B/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B081RH8C7P/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

If you are going to splice, you really should go with aerospace style PDIG splices from a reputable source such as:
https://bandc.com/product-category/electrical-supplies/terminals-and-splices/

These have one piece (not split) barrels that are long enough to take the double crimp from a tool like this:
https://bandc.com/product/pidg-style-crimp-tool/

These crimpers make two crimps at once - one on the conductor and another slightly larger crimp on the insulation providing both a gas tight connection and strain relief.

Ed

mcamera

08-05-2023, 06:06 PM

I've read through some alignment threads but most are a decade old. What are the specs you guys have been running or found to work best? I'm getting my car re-aligned on Wednesday to hopefully get my car to feel less darty/nervous and a little more planted during turns. Going slightly more aggressive to help with autocross also, but this is mainly a street car.

Current specs
If I'm reading this right, I have one toe in and one toe out on the front? It's not much, but I would think that could contribute to some of my steering nervousness? I think this is basically zero toe but I would like them both to be facing the same direction, toe in.
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I want to go to these specs, but any suggestions? Again, 90% street car but also some autocross.

Front
-1.2deg camber
+5deg caster
1/16" toe in

Rear
-1deg camber
1/8" toe in

Ajzride

08-05-2023, 07:03 PM

Those specs should be fine for a street car, if the alignment shop can get them there. I've been away from my project too long but I seem to remember having to modify the UCAs to get there (but that might have only been for early chassis).

mcamera

08-06-2023, 08:51 AM

Yeah I saw that early builders had to cut some pieces or add spacers to get high caster and camber. Wasn't sure if that was still an issue with the later kits like mine from 2020. Guess we'll find out.

I noticed between my first 2 alignments that 4deg caster was better than 3deg. So I'm going to focus on higher caster and add a couple extra washers to my bump steer kit to try and work out the last bit of bump steer.

Ajzride

08-06-2023, 10:01 AM

I have 5 degrees of caster, 1 degree of camber, 3/16 toe and the car handles great for street driving. I have the Baer bump steer kit modified to accept large spacers, so I have almost no bump steer (this was critical for the roads where I live).

mcamera

08-08-2023, 09:22 PM

Thanks for the reference AJZride!

I added 3 washers to my bump steer kit to bring my total spacers up from 21mm to 27mm. This is the most I could add to the Baer kit without modifying it. The car is significantly less nervous already. I must be getting close to same travel path for suspension vs steering. Adding these also increased my toe in though so that may be helping. I have my alignment appointment tomorrow morning and will report back.

188531

Ajzride

08-09-2023, 07:31 AM

188546

188547

driveslikejehu

08-09-2023, 07:47 AM

Similarly, my front specs are; 6deg caster, 1.5deg camber, 1/16 toe
I also added all the washers I could to the Baer system and don't notice any bump steer, though I'm unfamiliar with it so may have some.

mcamera

08-10-2023, 07:42 AM

https://youtu.be/a6s48XXZVaE

mcamera

08-11-2023, 10:33 AM

Got the car back from the shop with the new alignment. As expected, they maxed out a couple adjustments. Front camber is maxed at -1deg and caster is maxed at +4deg. With the added caster and extra spacers on the bump steer kit the car is significantly calmer. Every little steering input doesn't make the the car dart in that direction and the steering wheel is finally starting to pull back to center a little bit after turns. Bump steer is gone for most driving but large bumps/bridge transitions still give the steering wheel a little shake. Much improved and worth the time and money. Still not as good as a production car but this is closer.

The car is already easier to drive on back roads but the true test will be this Sunday at autocross. We'll see if I can close the gap to those pesky Miatas with my modest alignment changes. While doing my research I learned that increasing caster also gives you more negative camber while turning. A nice side effect. So maybe I'm effectively running more than just -1deg at the front wheels during turns. Hoping this helps my front end stick better! It's my limiting factor right now.

188648

I also had a CEL pop up this week for the air pump valve. I cleared it and will see if it comes back. I deleted most of the air pump system so hopefully this isn't actually effecting anything.

188649

J R Jones

08-11-2023, 10:45 AM

One can only appreciate so much from a driving video. My guess from your video is the limiting factor in cornering is oversteer. If the back was holding better you could go faster.
As mentioned by Sgt Gator previously, setting up the rear lateral links is critical to snap oversteer. They must be equal length forward and aft. Right to left is not critical.
With that, you could explore more front anti-roll bar influence. With the Subaru/FFR bar you do not have many options. Modification of arm length can create more effect.
Higher front spring rate is another possibility.
jim

Dave 53

08-11-2023, 12:03 PM

https://youtu.be/a6s48XXZVaE

I was watching the autocross at Sonoma earlier this year. They had a "dynamic" course. If a cone got knocked out of position, it didn't get fixed so the course evolved throughout the day! Obviously, the children were in charge (not saying that's a bad thing).

mcamera

08-11-2023, 01:36 PM

It's hard to tell from the video but I'm actually getting understeer. My front wheels give up first and the nose pushes through turns. I've increased camber on the front wheels (went from -0.7deg to -1deg) and increased the caster (+3deg to +4deg) which also adds camber during turning. Hoping that transfers more weight into the front end for more grip. I've considered disconnecting my front sway bar also.

That would be interesting with the cones moving around every run! When my times stopped decreasing I started wondering if I clipped a cone and they added a +1sec penalty. I don't think I did but it's hard to tell when you're driving.

BigDanSubaru

08-11-2023, 02:51 PM

It's not an easy thing to master and might have less of a benefit at the lower speeds of autocross, but trail braking will help keep weight down on the front tires and significantly aid in your ability to grip and turn in. I've been practicing this technique on my simulator and it is super effective when done correctly. Also, since you are in second gear the entire time, you could left foot brake which might help a bit.

Dave 53

08-11-2023, 03:55 PM

I like to walk the pits and see what tires everyone is using. What are those Miata's running? Tires make a HUGE difference.

Do you have a limited slip differential? It makes a big difference in pulling out of a second gear turn. Do the Miata's?

I see some understeer going INTO turns. That understeer might be that you are doing some trail braking with too much front brake bias. Your stop at the end of the first run and other places too looks / sounds like too much front bias. Maybe find a stretch somewhere and get your brake bias dialed in. If you switch up tires, recalibrate your brake bias. It also explains your comment. "the front wheels give up first". If your front tires are squealing the way they are as you brake for a turn, the squealing probably means loss of traction as you tun in due to the brakes locking up so easily.

mcamera

08-14-2023, 07:55 AM

All excellent suggestions. Everybody I've talked to is running 200 UTQG tires. My Kumho's are 460 and most people have said switching to 200's dropped their times anywhere from 3-8 seconds! I've been comparing myself to the stock classes because they're limited to street tires (no slicks) and can't make many modifications. That way I can see if I'm gaining on cars that are the same every race when I modify something.

I don't have an LSD so I occasionally spin 1 wheel in sharp low speed turns. I think I would benefit from one but I also think stickier tires would be enough to eliminate those spins. I have modest power from a stock EJ25 tuned to 275hp/300tq and the longer gears of the 5spd.

I meant to play with my brake bias this weekend but forgot. I was distracted by my new alignment which has made my car way grippier than I expected. I didn't think I would notice a difference because my changes sounded small, but the car has come alive. I had a lot more control and speed in the slalom, the front end doesn't push any more in hairpins, and I'm able to get tail happy if I get on the gas too soon at exit. This was a huge leap forward and now the car feels as sharp as I always thought it should. Results will be shared in one of my next videos.

188785

mcamera

08-18-2023, 02:13 PM

My buddy let me borrow his set of Longacre scales to corner balance my car and I'm shocked at what I found. I didn't realize how poorly balanced my car would be. I thought corner balancing was one of those "squeeze the last 2%" out of something deals. My ride height was 4.5" at each corner (within 2mm of each other) but apparently even ride height doesn't translate to a balanced car.

First off, my friend's track car. Pretty cool little single seater with a 1200cc Yamaha engine.

189036

Here's the set of wireless scales w/ tablet. He also let me borrow 4 of these red tools to measure ride height. They stick magnetically to the bottom of the car and give you an easy read out on top.

189037 189035

Here are the car's weights without me sitting in it.
- Front 43% / Rear 57%
- Left 50% / Right 50%

189038

And here are the readings with me sitting in the car
- One of my rear wheels has 200lbs (26%) less weight on it. This might explain why it's so easy to do a 1 wheel peel. With no LSD, once 1 wheel spins I lose acceleration.
- Even with me in the driver seat, the LF wheel has 130lbs (23%) less weight on it than the RF wheel. During a hard turn I can only imagine 1 wheel gives up way sooner than the other. Not using both front wheels efficiently.
- The left wheels have a 300lb (43%) difference
- The right wheels have a 0% difference
- The diagonal and cross weights are 43% / 57%. Far off from 50/50 as you want.

189034 189033

Final results after adjusting my coilovers
- Front wheels are 5% different (old 23%)
- Rear wheels are 6% different (old 26%)
- Left wheels are 25% different (old 43%)
- Right wheels are 24% different (old 0%)
- Corner weights are 50/50 (old 43/57)
- In the end my ride height is ~10mm higher on the passenger side but my body is level and measurements from the fenders to ground are similar. Build differences + the hand welded chassis probably has some warp.

189032

The difference when driving is huge. It turns with so much more confidence and accelerates with less sliding now that both back wheels are working together with similar grip. The ride has gotten noticeably stiffer now that all 4 shocks are loaded evenly. I can't wait for autocross next weekend. I'm expecting big results.

FFRWRX

08-18-2023, 04:30 PM

Very cool equipment and interesting findings. I felt the same way you did, that corner balancing was a final tuning that really didn't have major effects. I'm also surprised that it doesn't take much change in ride height to make significant changes in corner weight.

mcamera

09-05-2023, 07:12 PM

https://youtu.be/w_brzs9bPIY

mcamera

09-19-2023, 08:08 PM

lpmagruder

09-19-2023, 09:02 PM

Marketing to sell a very high margin item :-)

J R Jones

09-19-2023, 09:54 PM

I never heard of any equivalency for rotating mass. We did road race SBF with aluminum flywheels saving weight and rotating mass. The result was faster free revving with no load. Helpful for rev matching downshifts.
jim

idf

09-20-2023, 07:42 AM

BigDanSubaru

09-20-2023, 10:18 AM

Does anybody else feel like this is optimistic? The crank pulley is the same diameter as the OEM pulley so it still has to produce the same amount of torque to turn the alternator on our cars (and maybe the AC for some people). You can make the pulley lighter but to say it reduces so much rotating mass (-4lbs) that it's equivalent to 100lbs off of the curb weight sounds like a stretch.

190276

Mike, I do not recommend installing a lightweight crank pulley. These are fancy looking, but do not serve the function that is intended for the crank pulley. The OEM crank pulley is a harmonic balancer. Those lightweight ones do not harmonically balance at all. If you want to swap your crank pulley, look into an a Fluidampr Harmonic Balancer or an ATI Super Damper. The Fluidampr is superior, but more expensive. Both will be significantly more expensive compared to the lightweight options, but will actually help your engine rather than hurt it. Talk to any reputable engine tuner and they will tell you the same thing. If you cannot afford a Fluidampr or ATI Super Damper, just keep the stock balancer/crank pulley (which is what I did). At stock power levels, the OEM balancer does just fine.

lance corsi

09-20-2023, 10:29 AM

I agree with BigDan. Use the oem damper, your crankshaft will thank you. In fact, a bit more rotational weight is an advantage you will notice in normal driving. More tractable at low speeds and takeoffs. The low rotating mass of a 4 cyl engine and low torque makes this more evident. I resisted the urge to go with a light flywheel for the same reason since I will use my car more for a gt than a track car.

mcamera

09-20-2023, 10:42 AM

idf
Quote Originally Posted by mcamera View Post
Does anybody else feel like this is optimistic? The crank pulley is the same diameter as the OEM pulley so it still has to produce the same amount of torque to turn the alternator on our cars (and maybe the AC for some people). You can make the pulley lighter but to say it reduces so much rotating mass (-4lbs) that it's equivalent to 100lbs off of the curb weight sounds like a stretch.

Attachment 190276
I have that pulley in red in my 818. It looks way faster.

Hahaha that sounds more accurate than the advertisement

I believe lightweight flywheels reduce enough rotating mass to make a noticeable difference. Those usually save ~12lbs and still have to turn everything between the engine and wheels. Same concept here with the crank pulley.

From reading many threads, there are claims that Subaru doesn't use their crank pulley as a harmonic damper. Including some emails from Subaru customer service saying it's just a pulley, not a damper. That being said, I agree any benefit is probably small enough to not be worth the risk or $150.

lance corsi

09-20-2023, 11:44 AM

BigDanSubaru

09-20-2023, 12:13 PM

If it’s just a pulley, why does it incorporate the rubber isolator? It may not be a “harmonic balancer” but it is there to absorb secondary vibrations that are always present on a 4 cyl engine without a balance shaft.

Agreed, Lance. If it were just a pulley, there are cheaper ways to make them. Check out this very informative video of experts talking about the differences. MotoIQ is awesome, and they also have a video on performance alignments that may interest you for improving your autocross experience. Although they are quite aggressive settings in terms of tire wear for normal street driving.

https://motoiq.com/watch-what-harmonic-balancers-do-and-why-you-need-one/

mcamera

09-22-2023, 08:16 AM

I never noticed the OEM pulley had a rubber isolator on it. I never took it off for anything in my build. I agree some extra weight and damping is better.

lance corsi

09-22-2023, 11:33 AM

Wise decision Grasshopper!

mcamera

11-20-2023, 03:35 PM

Hello!
Autocross season has come to an end and I'm planning a few upgrades for this winter. If I'm not driving, I want to be building :). The biggest change will be switching from my cheap 460 treadwear Kumho tires to some sticky 200 treadwear tires which everybody runs in non-slick classes. I'm expecting this to make me a lot more competitive.

I'm also expecting this to start pushing the limits of my oil system. I know many of the track guys drop big $ on a dry sump but I'm looking more at an Accusump. For the price difference and limited time I spend at autocross, this is a better fit for me. I will pay for the electronic valve to make life easier, but does anybody have any good/bad experiences with this setup or any brands?

I can't confirm these numbers but I saw a thread online claiming the WRX motor can move up to 0.8L of oil per second (assuming max flow rate). So the 1L Accusump I'm looking at will probably only offer help for a few seconds (assuming pressure isn't a complete flatline at 0psi for 1.25 seconds).

But then I saw a claim by Killer B that their standard oil pan is good up to 1.6g's which is cheaper, simpler, and a better solution that doesn't wait for a bad condition to try and fix it like the accusump. Anybody have experience with this pan? It holds 40% more oil so will it hang out the bottom of the frame and be easy to damage? Pic of the claim below.

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Dave 53

11-20-2023, 06:23 PM

I can't remember why, but at the time I researched it, I concluded an Accusump was not in my future.

The OEM oil pressure sensor is very sensitive. It will trigger if oil pressure drops below about 10psi for even a momentary split second. The problem is, the oil pressure dash light will illuminate only for that split second. No one is staring at their gauges while going around a turn to see if the dash light lights. And an oil pressure gauge will not pick up a momentary drop in pressure in any meaningful way. I wired in an Amazon sourced: "Mini Timer Time Delay Relay .1 Sec to 400 days. 3V 12V 18V 5A. Power on or Off Delay, Cycling and More. Compatible with B00PD65UGA." I programed mine to flash the oil pressure light for 15 seconds if the oil pressure sensor triggers for even a split second. That way I'll be alerted to a momentary drop in pressure after it happens. I think this is a good setup on a track car. Maybe do that first and you'll discover you don't have any oil pressure issues. If you're not having fuel starvation issues in right turns with less than half a tank of gas, your oil pressure probably is fine (at least with FFR gas tank - not sure how the Boyd tank behaves).

A Killer B or some other robust oil pick up tube is a good idea as the OEM one has a reputation for breaking which will starve the engine of oil.

I have a Killer B pan (and pickup). It holds about 1 extra quart of oil. I put a 1/2" block between the motor mount and motor to raise the engine so the pan passes above the frame rails. Can't go any higher than that otherwise my turbo hits the bolt on engine compartment cross member. I also have an Arctangent oil control plate. No issues in long (8+ seconds) high G turns.

mcamera

11-21-2023, 09:02 AM

Thanks for the feedback Dave. I start my autocross events with a half tank of gas and at the last event I had fuel starvation on my last 2 runs. There were back to back left hand hairpins, and the engine cut power in the same spot twice. Coincidentally I got 8 runs that day instead of the usual 6, so I may have been getting close all year without knowing it! No problems since on the street. I have a Boyd tank and this is with my cheap 460 treadwear tires. Switching to grippier 200 TW tires will make this worse.

I have the Killer B oil pickup tube already so all I would need is the pan. Adding a spacer to the engine mount is a good idea. My ride height is 4.5" so I'm not super low which helps. I'm leaning towards the Killer B oil pan with windage tray. Even if it's not perfect it should be a big improvement over the stock pan.

Bob_n_Cincy

11-21-2023, 10:50 AM

'm looking more at an Accusump.

I have 2 almost new accusumps. One 2 quart and the other is a 3 quart.
I make you a deal you can't pass on.
Bob

BigDanSubaru

11-21-2023, 03:08 PM

Both Killer-B and IAG make great oil pickup, windage tray and baffled oil pan solutions. I am running the Killer-B on mine. Can't say much about how well it works because it isn't running yet.

blomb11

11-21-2023, 03:47 PM

Sounds like you may have some fuel sloshing as well. I am not sure if you can open up the Boyd tank to add fuel foam to help reduce the sloshing. Otherwise maybe a surge tank is an option. I added Holley hydramat and foam to the FFR tank to prevent sloshing. I also have the IAG oil pickup and windage tray installed. I am close to my first track day shakedown to see how it all works.

Dave 53

11-21-2023, 05:25 PM

I have a Holly Hydromat in my FFR tank, but no foam. It didn't save me from needing a surge tank.

I know the guys that made them don't make them anymore I don't think, but, it would be worthwhile to see if you can hunt down an arctangent oil control plate.

Bicyclops

11-22-2023, 12:07 AM

I went all out with a Radium surge tank and dry sump.

Ed

mcamera

11-22-2023, 12:14 PM

Thanks for the offer Bob, but I've decided to go with the KB oil pan and windage tray. Looking to keep it simple by swapping parts instead of adding, and preventing the problem instead of constantly supplementing one. That's my thought process at least. I appreciate it!

The Boyd tank (as of late 2020 when I bought mine) has some new baffles that prevented me from adding a hydramat. Diagram from an earlier post in pic below. I started my day with a half tank (5/10 gal) and it only starved on runs 7 and 8 (plus an hour of idling at that point). My blind guess is my tank starved around 4 gal? The easiest fix for me is to show up at autocross with more than a half tank of gas. I'll start with a 3/4 tank in the Spring (7.5 gal) and see if that gets me through my runs. If not, full tank it is!
192572

blomb11

11-22-2023, 05:50 PM

Ah I missed that part about starting with only a half tank. Definitely fill it up before your first run!

mcamera

01-07-2024, 11:07 AM

With the holidays over and after a crazy amount of travel the last 6 weeks (Cleveland, Miami, Key West, Detroit, Toronto, Central KY, Vegas, Detroit) and catching Covid again... it's time to start chipping away at my winter projects!

https://youtu.be/JJkRnw-M9jI

Dave 53

01-07-2024, 03:37 PM

I had the same rubbing on the control arm. It took 10mm of spacers for me with 255 tires. I put witness paint on the control arm rubbing spot to keep an on going check. On track, I'm still getting just a tiny bit of rubbing, but I can't see any indication of it on the tire. The rubbing was really bad before I put in fresh bushings.

Some simple Google research turned up that with our 12mx1.25 studs, we need a minimum of 9.5 turns on the lug nut. I assume that means full 360 degree turns (it looked like your count was the number of half or 180 degree turns). I was able to install longer studs on the rear hubs without removing the hubs from the car. It required cutting the anti-lock brakes sensor ring off. The front requires hub removal to switch out studs.

mcamera

01-17-2024, 01:35 PM

I bought my spacers from FastWRX and they say you can run the 5mm spacer on stock studs as long as you have at least 12mm of thread engagement. But I have aftermarket wheels so I double checked. I measured 12mm on the stud and that took 6 turns for my lug nut to reach. I put my wheel and 5mm spacer on and my lug nut took 7 turns to torque it down so I have enough engagement by their standards.

I'm upgrading my front lower control arms to the aluminum STi arms. My tire currently rubs the wheel well at full lock, even with my skinny 215/40 tire. This tire also looks bad on my 18x8 wheel because the rim sticks out further than the tire. The wheel also sits too far back in the wheel well and looks bad. Adding a wheel spacer isn't an option because it makes my interference even worse. Finally, I maxed out my alignment at 4deg caster and want more. When I updated my alignment from 3deg to 4deg I noticed an improvement in driving stability. I'm sure another 1-2deg will be even better.

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Before and after the arm. You can see the wheel has moved from behind the centerline of the wheel well, to in front of the centerline. Probably moved 1/2"-3/4" overall. This gave me more clearance to the panel that the back of my tire was rubbing.

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With this extra clearance I mocked up a 10mm wheel spacer to push the wheel out and increase clearance to that panel. I've ordered 10mm spacers and longer studs since this looks good. I'll check after those are installed and I'm hoping I can bump up to a 225 tire. Even if that brings back my tire rubbing at full lock, my bigger issues will be solved.

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Sgt.Gator

01-17-2024, 03:00 PM

If you haven't bought the pan yet I would look at the new IAG Competition pan or their new street pan. The comp pan has many features that should work well, but may hang too low. I think the design is superior to the KB pan.

On the studs, you may want to make a project out of swapping all of them out for the ARP extended studs. My buddy just lost a wheel off his LGT track car when the oem studs snapped off at Area 53, it was costly. It's pretty easy to drive out the old studs and set the new ones if you have the right tools. I've never heard of an ARP stud failing, but seen multiple oem studs fail at the track, three times at AutoX events! (All makes, not just Subies). The extended studs give you lots of options for spacers too.

Edit, Whoops, missed that you had ordered the extended studs!

mcamera

01-18-2024, 01:47 PM

I already have the KB oil pickup so I'm going to stick with the KB oil pan to make sure everything is compatible. I added upgraded studs to my list for rear wheels though. Was going to leave those stock.

I'm looking at tires and my options are very limited. I'm only expecting there to be room to bump up my front tire to a 225/40/17. The only 200TW tire in that size is the CONTINENTAL EXTREMECONTACT FORCE. But they don't make a 255/35/18 to match. They only have a skinnier 245 or too big 275.

But several other brands make the 255 I need to fit my car perfectly. How do we feel about the fronts being Continentals and the rears being Falkens? Seems against etiquette but if they're the right sizes and same treadwear rating (I know this varies a little between brands), I don't see this causing any issues.

Bob_n_Cincy

01-19-2024, 02:23 AM

I
On the studs, you may want to make a project out of swapping all of them out for the ARP extended studs.

before my 818 we autocrossed a 2007 NA impreza. Heat and cool cycles of the brake rotors would cause center of the aluminum wheel to expand and contract. this would stretch the oem wheel studs until the lug nuts could not be removes without snapping them off. Probably one or 2 studs a weekend. in 2013 switched to the ARP Studs on all our subaru's. Problem solved.

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Rob T

01-19-2024, 06:32 AM

I remember going through a lot of gyrations trying to switch from Hoosiers to something different. I found that the normal tire ratings/size did not always translate into exact dimensions for the tire. I found that some of the manufacturers provided actual dimensions, especially for diameter that proved invaluable.

mcamera

01-19-2024, 04:17 PM

J R Jones

01-19-2024, 04:45 PM

I went to half a dozen autocrosses this year. About 70 cars at each event and I had no studs break, no lug nuts seize, and never saw anybody else have a failure. Am I not driving fast enough lol? I was on cheap 460TW summer tires so maybe I just wasn't able to create enough grip/heat to cause problems.

TireRack shares all of the dimensions for the tires I'm looking at. I need to check my tire clearance again with my new LCA's and my current 215's though. I realized when installing the passenger side LCA that the rear bushing mounts are not symmetrical. One side is 1/4" longer and will move the wheel forward a little more in the wheel well. I need to go back and flip the rear bushing on my driver side LCA.

I recently swapped my 2002 steel LCAs for 2006 alloy LCAs on my 2014 chassis. With the front pivot through bolts installed the rear "Z" bracket was 0.75 inward from the mount brackets on both sides.
I had to elongate the front bracket holes to eliminate side loading the isolators.
BTW the "Z" bracket installs with the smooth tab up and the stepped tab down. Not the same as Subaru orientation.
jim

Dave 53

01-19-2024, 11:37 PM

I've got 32 track days with 215 front's, 255 rears. Last two sets, Falken RT660. Front grip has not been a problem. The only time I get understeer is in the rain or a (California) cold track on cold tires - occasionally only the first warm up lap of the day. I have no plans to go wider. Maybe it's different on a slower / tighter autocross track?

mcamera

01-20-2024, 08:05 AM

JR yeah I realized the smooth side up on the Z tab was the better way. Need to flip my driver side around since I did that one smooth side down. I also had to elongate the holes on the Z tab a little to help with the install.

Dave I agree with your notes. I don't have understeer with my 215's. They give me enough grip to make my rear tires the limiting factor. At this point I want wider front tires because they'll look better on my 8" wide wheels. Currently my rim sticks out further than my tire bead. The tire looks stretched and kind of dumb.

J R Jones

01-20-2024, 11:45 AM

mcamera

02-19-2024, 07:40 PM

https://youtu.be/aghTaWpteYc

mcamera

02-29-2024, 05:44 PM

https://youtu.be/38P6X5_n2Yc

Dave 53

02-29-2024, 06:53 PM

Bicyclops

02-29-2024, 11:16 PM

Something to consider with the 818 is it deletes the fore and aft top engine / transmission brace (I forget exactly what it's called).

It was impossible to see with a casual inspection, but I discovered my timing belt cover was all bashed up. I concluded that without that top brace and the soft OEM mounts, the engine was free to move forward and slam the timing belt cover against the coolant piping. Perhaps someone can repost the video of the engine movement at an autocross.

I used the stiffest Cusco through bolt engine and transmission mounts available. The next step is solid mounts. Vibration is absolutely not an issue and my timing covers are still intact. These cars need more than the OEM mounts just to make up for the top brace delete.

I think that most call it the dogbone. I went with the stiff Cusco mounts, and they are stiff. I had a belt adjuster pulley come loose and embedded the pulley into the timing belt cover. Yikes! Fortunately I heard the noisy belt when I was putting her back in the garage before it came all the way apart. My scavenge pump woulda quit and I would have been very sorry. Changing out the cover without pulling the engine wasn't easy.

On another note about movement, my car had started pulling left under acceleration and darting right when I would lift for a shift. I've got nearly 3Kmiles on her. It was getting scary so I did another string alignment on it and it got a lot worse. I took it to an alignment shop and they got it straight but discovered that with it up in the air, you could shake the left rear wheel substantially. Pretty scary stuff. I got it home and found a lot of loose bolts. The jesus bolt through the lateral arms was the worst of them. I know I had all of them tight. I'm going to start checking all the suspension bolts every thousand miles. I do drive it hard on canyon roads. Lots of side loads.

Ed

Ed

mcamera

03-01-2024, 12:11 PM

Dave, that's why I went straight to the stiff rubber mounts when I built the car. I know all OEM mounts usually allow a lot of movement and I didn't know what would hit, but I suspected something could. The poly mounts will deform over time so I prefer solid/stiffer rubber mounts which I have more experience with. Glad to hear the vibration isn't bad for you, I've had several friends switch back from poly mounts on their street cars because the vibration was too much.

Ed, the thought of things shaking loose has crossed my mind but I haven't found anything yet in 2 years / 2k miles. I'm expecting to find something now that I autocross the car more often and I'm about to switch to stickier tires. It's going to be harder on everything.

Bicyclops

03-02-2024, 12:05 AM

I guess I should have expected stuff to loosen. I do a lot of second gear roads (so twisty that I just can't get into third) that are fairly bumpy. Gonna check all the suspension bolts every thousand miles until I gain some confidence that I could go 2 or 3K. It'd be good if I could trust it to the next oil change. ;-)

My first ride was a hardtail Triumph motorcycle that I bought in a basket. I had to tighten stuff on it every day and even then I kept losing stuff off it. I was dumb enough to mount my ignition coils on a cantilevered piece of sheet aluminum. One day I glanced down and they were hanging from the plug wires a quarter inch off the road. My first lesson in metal fatigue.

Ed

mcamera

03-15-2024, 12:39 PM

https://youtu.be/7bgw1oIZA2M

mcamera

04-14-2024, 02:43 PM

https://youtu.be/h7TXGgeD1iY

lpmagruder

04-15-2024, 10:12 AM

I thought we were in E Modified? That's what I've been running at least, but the PAX is killing me.

I've been on the fence about classing as XB. My car is technically a little under weight minimum, and XB classing specifically mentions having wipers and a heater, which I have neither. There also a bunch of wording for "finished" interior which I don't think my bare metal panels would pass...

Probably at a local level no one cares. Has anyone questioned your classing at the event you go to?

mcamera

04-15-2024, 11:09 AM

At my first event last year the workers recommended the XA class. I found out the minimum weight was 2930lbs, so I switched to XB the next time because the minimum weight was 2330lbs. Like you said I'm still underweight (2280lbs w/ driver) but much closer. If I fill my gas tank 100% I should be within 20lbs.

198268

EM does list the 818 S/R, but not the C. And the minimum weight is only 1700lbs so I would be 600lbs over. Better for me to add 20lbs and stay in XB if that keeps me legal. Nobody has said anything because I'm not the fastest in XB. I'm not a threat yet lol.

198264 198266

lpmagruder

04-15-2024, 01:48 PM

Yeah same here. I'm not good enough to threaten anyone locally in XB. I think before next event I'm just going to ask in the FB group if anyone minds if I reclass. Just nice to have someone to race against (so far I've been the only EM car at any event I've gone to) and with EM PAX I'd never be even near competitive.

mcamera

05-26-2024, 10:33 AM

https://youtu.be/GT6TJGJmDyI

I finally made the jump to good track tires and I am not disappointed! I can't believe how much more grip these have.

aquillen

05-27-2024, 09:23 AM

Nice Vid on your tires and track time. I put this Walmart yoga mat 10,000 street miles back and it has held up for 4 years now, Thin and makes the wells quiet, pleased with durability and light weight too:

Wal Mart Brand: “Athletic Works” 68” L x 24 “ W x 3mm Black CL3792B

Searching on line 4 years since then... I didn't get a hit on the part number but search Walmart for this - it sure looks like the same stuff in a gray color. Image of material matches mine too:

Athletic Works PVC Yoga Mat, 3mm, Dark Gray, 68inx24in

Mounted it with this adhesive, which I used on my whole build. Never have had any problem with this stuff - top notch:

https://www.dltcorporation.com/product_p/litebond-2065c-1qt.htm

But I read good about this easier to get too:

https://www.homedepot.com/p/DAP-Weldwood-32-fl-oz-Original-Contact-Cement-00272/100125525

Dave 53

05-27-2024, 04:13 PM

Nice recap video.

I had 2 set of RT660's (just switched to V730's). At the track, I was looking for 27 psi hot. So, 37/42 seems really high, especially on our light cars. There's always the disclaimer that tracks and autocrosses are hugely different.

If you're getting uneven wear on the outside edges, at least on the rears, it's super easy to tune for it by dialing in more negative camber. I increase rear camber at the track by 2 full turns of the linkage adjustment, then put it back for the drive home. Fronts are more difficult to adjust camber, so I don't mess with it. But, I'm usually not trying to improve front grip or tire wear, so it's not an issue.

I'll be doing my first autocross next weekend at Crows Landing, CA.

mcamera

05-28-2024, 09:42 AM

aquillen

05-28-2024, 08:49 PM

As long as your rivets are along the perimeter, just cover a little less width so you can still see them. 90% less noise probably. I used screws for all that and left the edge of the mat covering them but not glued - the mat could flap but has not worn away so must not be doing much in the wind.

mcamera

05-29-2024, 09:38 AM

Good idea Art

Dave 53

06-03-2024, 12:08 AM

Thanks for the tips and links Art. I'm sold on that mat being a good cover, but I've been wondering if I want to cover the rivets in the wheel wells. Might make it harder to remove the wheel wells if I need to make a repair.

Dave, that's why I thought it was worth mentioning my tire pressures. They seem high but anything less was scrubbing my sidewalls. I started at 36psi all around thinking I would slowly lower pressures, but that's not how it played out. I'm glad to hear you mention camber because I think that's playing a bigger role now. I only have -0.5 degree on the rears which worked great on my old summer tires that had less grip. I think the new RT660's have so much more lateral grip that now my car is actually leaning and my tires are flexing/rolling. I agree I could benefit from more camber now, I'll add some to the rear like you suggested. My car currently handles close to neutral, but with slight oversteer. So adding a little grip in the rear should only help.

Let me know how your autocross goes. I'm curious to see what you think.

I did my first autocross today. The participants were all in which is awesome! I met a National Champion and a guy that's been auto crossing since the 70's. I respect the skill needed to be smooth and fast. Some amazing cars and huge tow rigs. Nice social aspect to it. I worked a corner with a nice guy and fellow first timer that just got his 4C. A great way to get to push the limits of almost any car with very low risk and very low bearers to entry (seems all you really need is a car and helmet). But, to be honest and with respect, not my thing. I did 10 - 37 second runs on a practice course and 5 - 63 second competition runs and never got out of second gear (only 4 of us newbies on the practice course - everyone else did just the 5 competition runs). Notwithstanding it just being fun to be at a car event, it's just hard to wrap my head around spending the better part of a day for 11 minutes of track time (most participants only got 5 minutes).

I'm happy there are options for everyone to find their car thing be it wheel to wheel race series, drag racing, drifting, time trials, autocross, HPDE, shows, rallies, rock crawling, whatever. I'm glad I finally got the opportunity to try an autocross, but I'll be sticking to HPDE track days with my 818 and 24 Hours of Lemons racing.

BTW, I also have about 0.5 degrees of rear negative camber for street driving. 1.5 turns of more negative camber on the rear camber adjustment and about 20psi front and 24psi rears (hot) gave me the best tire wear read on my V730 tires.

mcamera

06-03-2024, 01:10 PM

I can see how autocross would feel like a poor compromise for a full track but there's a huge convenience to it. I have 12 events less than 10 minutes from my house. I don't need to have a truck and trailer to get my car to a track 2 hours away. I just drive to the event, pay $45, race, and drive home. I agree it's not a lot of seat time but it's a different kind of challenge. Like qualifying vs racing. It also allows me to try new mods/setup changes without ruining a $300 track day. I would pay double if I could just show up for my heat and leave though because like you mentioned it takes up most of the day for very little racing.

I looked at the inside tread of my rear tires and 1" of it still looks brand new. It's never touched the pavement, even after an aggressive track day. So I turned my camber links 1 full turn which I measured as an extra -1deg of camber. So -1.5deg total now on the rear. A quick drive on the street felt much sharper and it was harder to break the tires loose, but I'll confirm this week at autocross.

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Dave 53

06-03-2024, 11:30 PM

They set up a long competition course and had a smaller practice course that was bigger than the courses I see set up on my track days complete with timing which cost an extra $20 (on top of $70) to have access to it. I'm thinking I could not show up for the competition and get 50+ laps in on the practice course. Wish I thought of that on Sunday. That would be worth the hour's drive to get there.

mcamera

06-05-2024, 12:49 PM

That would be more worth it. Give you time to learn the course and try to squeeze every last tenth out of your time!

lpmagruder

06-06-2024, 11:27 AM

mcamera

06-19-2024, 10:16 AM

https://youtu.be/e59jho6G4zY

I keep looking for bottlenecks on my car to make it faster at the track and this one seems like such a basic oversight. I've been watching the outside shoulder of my tires to dial in pressures and maximize my contact patch, but I didn't realize how much of the inside shoulder had ZERO contact with the ground.

It's hard to see at the track and I figured -0.5 degrees of camber on my rear wheels would be.... 0.5 degree past horizontal... favoring the inside of the tire slightly. I never thought I'd be adding a bunch of camber to improve straight line traction!

Obviously if I add too much camber I'll start lifting the outside shoulder and could reduce my contact patch in a straight line. However, what I'm seeing at the track is that I'm still overworking the outside shoulder vs the inside shoulder. Just have to find the sweet spot.

lpmagruder

06-19-2024, 06:38 PM

Fighting the same battle over here but embarrassing myself in EM instead of XB ��

I added a downright irresponsible amount of rear toe in and it made the car SO much more stable. If you're spinning look at that.

Dave 53

06-20-2024, 02:40 AM

I think if you go to an Autocross with drive time in your head as a metric, yeah it's going to be a huge disappointment. Think of it more like a social event, like a cars and coffee but you get to have some friendly competition at the same time.

There's also something to be said of getting out there and putting down a quick time in 4 or 5 runs on a course you've never seen before, drives you to better understand how your car handles instead of having memorized braking zones and lines on known tracks.

Also the cost. It's like 45 bucks where I live, on 2 day events with a class or Test/Tune on Saturday it's $80. If you live close it's really low barrier to drive there in you car, compete with good confidence that your car will be drivable to get home, all on the same tank of gas.

The idea that pretty much anyone in any car can have fun at an autocross at a low cost and with minimal risk to self and car is great! There are most defiantly differences between auto cross and HPDE. Pros and cons that everyone will weigh differently including drive time and cost being big ones. Seems autocross is burning $10 bills and HPDE burns $100 bills (and that's if nothing blows up). So yep, there is that. But, there are many similarities too including the social aspect of it and "understanding how your car handles" by pushing it and yourself to the limit. Ultimately, both are fun - pick your poison (or do both)! Golf... that's something I just don't get.

mcamera

06-20-2024, 09:38 AM

Haha golf is paying $50 for a 4hr nature walk, where you yell and curse the whole time. Unfortunately I know this all to well.

Dave 53

06-20-2024, 10:11 AM

Haha golf is paying $50 for a 4hr nature walk, where you yell and curse the whole time. Unfortunately I know this all to well.

Golf: Whack.... "****!"

Car: "****!"... Whack

J R Jones

06-20-2024, 11:11 AM

Last Saturday my son's buddies organized his bachelor party and I was invited. The first event was indoor electric go karts and it was vicious.

https://www.k1speed.com/

Steering is exceedingly heavy. You can't spin the wheels, and with rear brakes only, there is no understeer. Too much brake will cause oversteer. With equal power passing requires a strong offence. Sliding can be a defensive maneuver at the cost of lap time. Speaking of cost: about $26 for a ten lap session. I was arm/hand sore the next day.
It resembles a very tight autocross but either someone is humiliating you in real time or someone is all over your butt.
BTW the next sporting event was axe throwing. I do not endorse that as entertainment YMMV.
jim

mcamera

07-22-2024, 07:59 AM

Got a check engine light yesterday during my last autocross run. I think one of my TGV's is stuck. I put this off for 4 years but it might be time to look at options.

202102

mcamera

08-01-2024, 01:24 PM

https://youtu.be/g5IctlXyeu0

lpmagruder

08-01-2024, 04:31 PM

Bicyclops

08-02-2024, 01:03 PM

I'm curious what size and brand tires you have.

I'm really don't know what pressures I should be running on my low sidewall tires. 215/35R18 Pilot Sport 4S on Enkei 8" and 255/35R18 PS 4S on Enkei 9.5". Haven't made it to autocross or HPDE yet - just canyon roads and I am not an experienced high performance driver. This is my first sports car - and it's a monster! I've run 32lbs and as low as 24lbs and I haven't really been able to see any difference, but then it's hard to corner near limits when I don't know what those are. With 100' drop offs and canyon walls, I'm nervous to push it. Not the same thing as hitting cones! I've squeaked the outside front a few times. Felt like it was kind of skipping a little but not really sliding. I only broke the rear loose once cornering, but that was into a surprise tight downhill switchback and braking pretty hard to keep from hitting the mountain. I didn't have any time or room to countersteer, just had to get it stopped and take a breath. Easy enough to break the back end loose accelerating from a turn at a stoplight tho. ;-)

Ed

mcamera

08-02-2024, 03:31 PM

Wow, that's a lot of rear pressure!

I'm using a different tire but I'm seeing pretty good usage of the entire tire at autocross with 25 psi and just a degree of camber. I wonder what's so different between our cars, it doesn't seem like tire selection would make that drastic of a difference.

I'm using 235/40/17 Zeknova RS606 (go on, get your laughs out now, I'll get better tires next time) in the rear.

Lol I've never head of those but after looking they should be pretty grippy with a 140 tread wear rating. I'm using Falken Azenis RT660 tires. Another guy in my class with an MR2 (mid engine, similar weight) said he was at 36psi on his old RT660's. Even less pressure on his new Bridgestone RE-71's. My rear tires are 255/35/18 which I think are lower profile than his tires.

Mine are also a lot wider and slightly lower profile than your 235's. More grip = more leaning = able to use more camber. 1 degree of camber was better for my old 500TW tires that didn't grip nearly as much (so my car didn't lean as hard). Maybe the sidewall stiffness is that big of a difference between your Zeknova's and my Falkens? The track surface might also be grippier asphalt vs concrete.

The first time I ran these Falkens I started at 36psi and the tire wore all the way down below the indicator on my outer sidewall. No way I can lower my pressure right now.

I'm curious what size and brand tires you have.

I'm really don't know what pressures I should be running on my low sidewall tires. 215/35R18 Pilot Sport 4S on Enkei 8" and 255/35R18 PS 4S on Enkei 9.5". Haven't made it to autocross or HPDE yet - just canyon roads and I am not an experienced high performance driver. This is my first sports car - and it's a monster! I've run 32lbs and as low as 24lbs and I haven't really been able to see any difference, but then it's hard to corner near limits when I don't know what those are. With 100' drop offs and canyon walls, I'm nervous to push it. Not the same thing as hitting cones! I've squeaked the outside front a few times. Felt like it was kind of skipping a little but not really sliding. I only broke the rear loose once cornering, but that was into a surprise tight downhill switchback and braking pretty hard to keep from hitting the mountain. I didn't have any time or room to countersteer, just had to get it stopped and take a breath. Easy enough to break the back end loose accelerating from a turn at a stoplight tho. ;-)

Ed

Running on the street will be different than at a track and you're smart to not push it 100%! I wouldn't recommend super low pressures on the street. I haven't run your tire before but 24psi sounds way too low. You might crack a rim on a pothole or rough bridge crossing (ask me how I know lol). You generally want higher pressures ~35-40psi to give your tire strength for rough roads and to protect your rims. You will sacrifice a little tire contact/grip though.

On the track you can push the car a lot harder and lower pressures to maximize contact though. I use chalk on the shoulder of the tire to see how much of the tire I'm using during my autocross runs. It's a cheap/easy way to start optimizing your tire contact at the track. You can see in my video there's a triangle on the sidewall of my tire. You don't want your tire to wear below the tip of that triangle or you'll start using the sidewall of the tire which isn't designed to touch the ground. It also means your tire is too soft (underinflated) and flexing a lot!

lance corsi

08-02-2024, 06:25 PM

What is your rear toe-in setting? Could it be that toe-in is fighting you somehow?

Bob_n_Cincy

08-03-2024, 01:10 AM

driveslikejehu

08-03-2024, 08:09 AM

For tire pressure at track days (30 minutes runs with 60 minute rest between runs. We start at 20psi all around. then adjust between each segment to get even tire temps across each tire. Never more than a pound or two.

Pretty similar for me, tho I've only done a few track days. I've followed a few of these racing guys and used modest camber and tire pressure. I get it that autocross is very different with cold traction being so important.
I picked up an IR gun and measured pretty consistent temps across the width of the tires; a little higher on the left side on a predominately right turn track.
Anybody using data like that?

mcamera

08-05-2024, 02:41 PM

I was at 0.2 degrees rear toe in before I increased my camber from -0.5 to -2.5 degrees.

At autocross this weekend I lowered my pressures even though last time I tried it started to wear down below my sidewall indicator. It immediately wore down into the indicator, but my time was faster. So I dropped another 2 psi. It didn't wear much further but my time was faster again. So I dropped 2 psi again. The wear had plateaued but my time was even faster.

I started the day at 37 front / 40 rear. I ended the day at 33 front / 34 rear and placing in the top 20 for the first time.

The tires felt squishy at times and the rear hopped several times around a long sweeper, but faster times are hard to argue with.

202539 202540

mcamera

08-09-2024, 09:40 AM

https://youtu.be/S2j5L-SZ2q4

mcamera

08-14-2024, 10:04 AM

https://youtu.be/8fN_ohGMEqg

J R Jones

08-14-2024, 11:23 AM

Years ago I did exhaust development on my motorcycle in an attempt to reduce backpressure. Sound was not a priority. These days there are more baffling configurations to evaluate.
Anyway I had a non-destructive method of measuring exhaust options.
With a flow bench as inspiration, I used my shop vac to draw air through the mufflers or blow through them
A simple monometer between the shop vac and muffler measured static pressure. More drop = more restriction. This method can be used for intake systems as well.
I went on to measure dynamic pressure for air speed with a pitot to develop air boxes and ram-air at 150MPH.
Not as interesting but entertaining was measuring air flow in lawn mower decks.
Water and jet pumps are similar just alternative equations and math.
jim

Bicyclops

08-14-2024, 07:03 PM

It doesn't surprise me that you are having trouble with boost control and detonation uncatted. Everything I have read says don't unrestrict your exhaust or even your induction without a tune. Even just shortening the exhaust from the WRX long pipe setup has to be doing something. My 02 donor had a little downturn right behind it's downpipe and a pretty bad hitch in it's giggyup. Might have benifited from a tune, but I just drove it for a couple of months and cut it into pieces.

Ah, exhaust noise vs power. I go carted my car on the 818 adapter and stock catted downpipe. I had lowered the transmission mount for better lubrication and I didn't like the idea of where I would have to cut the bumper so I fabricated my own exhaust. I was given an aftermarket downpipe with a nice bellmouth and 3" piping by somebody who wasn't going to use it. I cut and modified it to run a pipe straight out the back of the car centered vertically in the lower cutout of the bumper and off to the right side. Talk about loud! I can't speak to horsepower on that version as I was running on a base tune which called for zero boost. I only got about the 12psi that the wastegate spring provided. I bought a Magnaflow straight through muffler with a 7" long body - not a lot of room back there and welded that in exiting in the same location. Still pretty damned loud and now had an annoying drone especially when letting off in the 4-5k RPM range. I bought a Car Chemistry 3 disc insert and stuffed it into the tailpipe. Much quieter and the drone was pretty much gone. Still sounded healthy but I didn't need earplugs anymore. Seriously - it made my ears ring more than my usual tinnitus. Still on the basemap tune.

I took it to my tuner and he said that it would cost a bunch of horsepower. The way the CC inserts are supposed to go in puts the can opener cuts towards the airflow which, he said, would effectively reduce the diameter of the pipe to that of the inner tube of the insert because of turbulence. I decided to turn it around to reduce that scooping effect. In the process of removing it using a slide hammer I beat the **** out of the inner baffle and tube. I then cut it off making it a 2 disc insert and put it back in backwards, reasoning that it might not be quite as restrictive that way.

Back for my tuning appointment, he was unable to fit his O2 probe into the baffle and removed it for the tune. I don't know how he has any hearing left after running it in his closed dyno booth with no ear protection, but I guess that's his problem. Anyway, he got 310 whp out if it on 91 octane pump gas and 386 on E85. He then stuck the baffle back in and ran it, probably just so he could prove to me how right he was about the power loss. It cost 24 hp.

Exhaust restriction is a thing. When you think about it, the guys who claim no power loss from these baffles (with V8s) and even that it has more low end torque are not mounting them behind turbos where every bit of restriction really shows up. Did I pull the baffle out when I got home? Nope. First, I like that I don't cringe and hurt from the exhaust note. Second, I like the way it sounds - it makes me feel like I'm in a British sports car on a B road. Third, 362whp is absolutely nuts in this light car. 290hp would be way plenty and that's probably what it will do on pump gas. It isn't going to overboost with the baffle in and it's already tuned for when I pull it out for HPDE in the fall. I am running it on the ethanol. It's cheaper at the pump and oh so much fun!

Ed

driveslikejehu

08-15-2024, 01:07 PM

I had a similar but different experience with a stock setup with just the catted downpipe and no muffler. After a track day last month I found the cat guts completely gone. Since it degraded and left the chat over some period, I didn't notice it being louder until unloading and backing in the garage. And definitely noticed the whistling.
Going easy around town no one seems to notice. Concerned about local track limits, we measure 94db at 10 yards under full boost and acceleration.
I haven't noticed any power changes, but as noted, I'm full stock ('06 STI), no tune.
For now, it's enough power; I'm still getting a handle on the thing at the track. All the years of traction control meant it was disconcerting to feel the rear start to break loose in a fast corner at top of 4th. (Time for aero I think)
A bit later I want to go your route and add boost, so I'll be watching how this evolves.

mcamera

08-16-2024, 10:02 AM

Jim, I used to do similar tests when I designed airboxes for the big 3 (Chrysler, Chevy, Ford). The air filter was the single biggest restriction, which is partially why filters have such a large area compared to the cross sectional area of the ducts. Didn't do any ram air work like you though. That could make things more interesting. No surprise that the cat is a restriction since it's just a thick filter for the exhaust. The honeycomb is so dense you can barely see through it.

Ed, yeah I expected some problems but wanted to test the sound before committing to a tune with a catless pipe. Glad I checked, the car was too boomy at low rpms and too loud at WOT for me. With just the cat on my car the sound is louder than a typical car but reasonable for a sports car. Still get some turbo whistling too which I like. I agree with you, some car guys will always say louder is better but there's a point where it makes driving more annoying than fun. Your setup sounds potent! You have plenty of power on tap even with your baffle in. I was trying to maximize my stock setup (235whp) / improve boost response for autocross, but this was not the way to do it for me. Now my thinking moves to a mild turbo upgrade with an electronic boost solenoid. Again, trying to maximize response and mid range power for autocross.

Driveslikejehu, that was one of my concerns too. I think I would have blown past sound. A stock STi engine still has plenty of power in these cars. I took a similar path in leaving my engine stock for 2 years (with just a tune). It was nice to learn how to drive the car first. I'm just now looking for more power because I think my driving is finally good enough to benefit from it. Tuning the stock engine was a huge improvement by itself. I didn't make much bigger peak numbers (+15whp), but my low and mid range torque grew a LOT (+60wtq). Made the car more responsive and I have way more useable power. Dyno pic below.

202806

Bicyclops

08-16-2024, 12:32 PM

Looks to me like you would benefit from a flatter torque curve. It's probably a function of your uneven boost control. I was told that I'm doing ~28psi on ethanol, much less I imagine on pump gas. I haven't been able to look at my boost gauge when I have my foot in it - too busy trying not to die. ;-)

Ed
202809

The blue curves at top are 75% ethanol. As you can see, my torque is pretty much there from about 3500 and falls off slowly with either fuel. I was told that most of the benefits are available above ~40% and that it'll run fine up to 100%. I'm currently at 80%. Incidentally, he also said that first starts in cold weather might take some cranking which in summertime SoCal isn't a thing. We'll have to see how it shakes out come winter.

mcamera

08-30-2024, 01:05 PM

203394

This weekend I had another great outing at autocross. I finished 2nd in my class and 17th out of 92 cars overall. I beat the class leader but I'll likely end up in 3rd for the year. Too little too late, but not bad for a pretty basic 818 build (tuned stock engine, upgraded front LCA's, and 200TW tires (215/255). A lot of my improvement has come from fine tuning my setup and learning to drive better.

As the autocross season winds down I'm starting to plan my winter upgrades. The most impactful but expensive upgrade I'm looking at is wider wheels/tires. Which requires new rear trailing arms but I can't find any info if aftermarket trailing arms give more tire clearance. I know the VCP trailing arms allowed up to 9.5" wheels but it looks like VCP has closed. The Cusco and Mooresport (MSI) arms don't mention anything about allowing wider wheels. Does anybody know if these (or any other arms) allow wider wheels?

https://www.flatironstuning.com/666-474-t
https://shop.mooresport.com/shop/msisub02-28-012-impreza-gd-rear-trailing-arm-set-25mm-correction-2576

I'm also looking at replacing the 17yr old rubber bushings on the rear trailing arms and lateral links. As I've improved the grip on my car, it sometimes hops around fast sweeping turns and exiting sharp corners. I don't think the old/squishy bushings are helping this. I like the stiffer STI Group N bushings instead of polyurethane mounts since they're maintenance free, won't squeak, and still offer a little compliance and isolation from NVH.

My TGV's are also throwing engine codes every couple weeks so I'll be replacing those with deletes this winter. Since the car will already need to be retuned, I'm also going to do an electronic boost control solenoid to improve my power band. Still debating on a mild turbo upgrade (VF48 HF or TD05-20G) while I'm getting tuned. I would want it to remain quick spooling for autocross, but hopefully power wouldn't die off at 4500rpm. The stock turbo has actually been great for autocross. Great response and low to mid power.

J R Jones

08-30-2024, 02:57 PM

mcam,
My previously unfinished 2014 kit has 255/35-18 Yokos on FFR? 18X8.5 wheels.
It came with FI/Cusco Trailing Arms and Lateral Arms. (4)
As I bought it there was less than 0.25 sidewall to TA clearance. I installed 1.5in wheel spacers for 1.625 clearance.

I am going to Acura J-V6 and control arm suspension so this stuff is available. I prefer selling as a package.
jim

203410

203411

Bicyclops

08-31-2024, 08:32 PM

I used something like the Godspeed arms and some adjustable lateral arms. Search "02 wrx adjustable trailing arms" or similar and you'll get a bunch of hits. I had to cheat all the spacers to the outside to move the arms inboard and get as much wheel clearance as possible. Had to cheat the spacers on the arm that goes up to the firewall too. I used 12mm wheel spacers with 9.5" Enkei wheels w/45mm offset. I wound up bending the arms a little bit more with a Harbor Fright hydraulic pipe bender to get just a little more clearance. I have 255/35 R18 Pilot sport 4S. The closest approach to the trailing arm is right at the rim. I think I could get maybe even 275s on there, but I'll need to wear these ones out first and so far, it doesn't seem like I need more tire.

From the pix, it looks like the Cusco ones are roomier than what I started with, but pricier too.

Ed

blomb11

09-01-2024, 10:21 PM

The VCP arms it turns out are simply the Godspeed trailing arms with a relief welded into them. I bought the Godspeed arms first and needed more space so then I ordered the VCP arms. When I received them I was able to compare the two and see the VCP arms were the same, but modified to allow for more space. You could do the same cut and weld in a relief or have someone do it for you. I am fitting 265s on a 9.5” wheel with 10mm spacers.

203519

mcamera

09-02-2024, 10:18 AM

Thanks for the info. I currently have 255/35/18 tires in the rear. 8.5" wheels with a 45 offset, and use a 5mm spacer to clear the stock trailing arm. I've had no issues with clearance to the fenders either. Good to know the vcp arms are modified Godspeed arms. Wasn't sure if those cheap arms would be reliable but lots of people have run the VCP arms. Might need to cheat the spacers like you mentioned with any of the arms if I want to go to 275 or 285 tires. Going to be tight!

mcamera

09-02-2024, 10:24 AM

https://youtu.be/83btfOvF250

mcamera

09-09-2024, 02:14 PM

I noticed something this weekend when checking my tire clearances. My rear tires (255/35-18) are already rubbing my wheel liner. My driver side ride height is much lower than my passenger side as a result of corner balancing so it's rubbing worse. I also think I've been hitting the bump stop on the driver side with as much rubbing as I'm seeing. That might be part of the reason I've felt the car hopping around high speed sweepers. My driver side shock is getting maxed out (instantly going super stiff) while the passenger side shock has a larger working range. Putting the rear wheels in very different, uneven conditions.

DRIVER
4.1" ride height
2" tire to liner clearance
1.75" shock travel before it hits the bump stop
203883

PASSENGER
4.75" ride height
3" tire to liner clearance
2.5" shock travel before it hits the bump stop
203884

My thoughts:
1) I could raise the car to give more clearance. I won't do this because it'll hurt performance, look worse, and my rear passenger shock is already maxed out.

2) I could add weight to the rear passenger corner and rebalance the car. This might allow me to reduce the height on the passenger side, which could level the body more and put the rear wheels in a more similar condition to each other. I'm about 30lbs underweight for my class so I'm not against adding weight, but this will likely just make the passenger side rub more like the driver side.

3) I need stiffer springs. This will reduce suspension travel, stop me from hitting the bump stop, reduce rubbing, and keep my tires closer to their nominal alignment where they have the most consistent contact patch. I think this is necessary to not only fix my current condition, but to allow for more improvements at autocross. It wouldn't be smart to put wider tires on the back right now which would take up more room and add more grip (more stress on the suspension) until I fix this issue first. Looks like the ride is going to get a little stiffer this winter.

lance corsi

09-09-2024, 06:57 PM

If you are using the supplied ffr Koni shocks, they are only vaguely adjustable and difficult to adjust damping. May I suggest the QA-1 shocks? They are externally adjustable, so no need to remove and disassemble in order to change damping and they offer a double adjustable for both compression and rebound. A bit pricey but for what you are doing, I think a worthwhile consideration.

Bicyclops

09-09-2024, 07:00 PM

I was feeling my rear suspension bottoming and there was evidence of rubbing in the wheel liners. I went to Eibach 425lb springs in the rear. While I was at it, I added thrust bearings under all four. It makes it so much easier to adjust ride height.

Ed

Bicyclops

09-09-2024, 07:02 PM

Lance,

Do you have a part number on the QA-1 shocks. I was looking but didn't really come up with one.

Ed

mcamera

09-10-2024, 10:58 AM

Yeah I'm still using the FFR coil overs and can tell they're basic. Thanks for the suggestion. I don't know much about shocks so I'm doing some research. External adjustments look like a great feature. I've learned how important setup is for racing this year so easy adjustments will be helpful to dial things in. The pricing doesn't look that bad, and they have options. I appreciate it!

lance corsi

09-10-2024, 01:00 PM

I’ll look at mine to see if they have a part number. Mine are dual adjustable and the springs I ordered to go with them are the same value as the Koni springs, although you may want a higher rate.

mcamera

09-13-2024, 09:06 AM

1 upgrade I know I'll be doing this winter is installing STi Group N bushings on the rear links/arms. I don't think my 17yr old stock bushings are up to the task. Should be a big improvement without the harshness and squeaking of poly mounts or upgrading to links with spherical bearings. Not to mention 1/4 the cost.

204099 204098

mcamera

11-04-2024, 09:45 AM

After my final autocross run of the year, I rolled into the grid with smoke pouring out of my car and somebody running at me with a fire extinguisher. Luckily we quickly found that the nipple on top of my coolant bottle had broken and sprayed my engine bay with coolant. No fire. It was cold outside (got down to 40 that night) and my tires were sliding and hopping aggressively every run until something broke.

206038

I was also significantly slower than the other guys in my class this race. I think the RT660's are really sensitive to cold temps. The MR2 I beat last time, crushed me and I know he runs RE71's. Even a FWD GTI with all season 300's matched my best time. I was pushing it but also might have been rusty from not racing for 2 months. Video to come.

I'm going to upgrade to the aluminum Mishimoto bottle
https://www.fastwrx.com/products/mishimoto-aluminum-coolant-expansion-tank-for-subaru-wrx-2002-2007-and-sti-2004-2016?variant=25315809808

Dave 53

11-04-2024, 12:52 PM

mcamera

11-04-2024, 03:06 PM

I started the season at 40psi but the last few races I've been running 30psi (cold and hot). I tried 28psi on my last 2 runs to see if my times improved but they didn't. Ran 39.7 on all 3 of my last runs. One of those runs was even with a 230lb passenger. The car just felt slippery compared to the hot summer races I've done all year. My temp probe showed the tires never got above 90F yesterday.

The car also hops more with the lower pressures. My times have proven there's more grip with 30psi vs 40psi but I think the extra grip is pushing other things past their limit and causing the hopping. My springs are maxing out and bouncing off the bump stops and I'm guessing my 20 year old rubber bushings are flexing a lot. All are getting upgraded this winter.

I was hoping to run the RT660's for 1 more season but if they can't keep up in the spring, I'd be willing to give the V730's a shot.

mcamera

11-05-2024, 11:45 AM

Found a little info to support my theory that the RT660's are more sensitive to cold than other 200's.

TireRack says their optimal temp is 120-130F. My tires never got above 90F.
206126

Grassroots showed the RE71's running a full second faster when stone cold vs the RT660's best time of their test.
206127

mcamera

11-28-2024, 10:30 AM

https://youtu.be/wHPpgnfHuYI

mcamera

01-06-2025, 09:40 AM

Winter upgrades have started. Here's the plan to get in the top 10 for autocross this year (18/100 last year).

- New dual adjustable QA1 dampers

- Stiffer rear springs to reduce body roll / stop tires from rubbing the fender (275# to 500#). I used a dynamics calculator to find the optimal spring rate and 500# should be appropriate.

- Upgrade rear suspension bushings to stiffer STI Group N rally bushings

- Longer rear wheel studs and larger wheel spacers to eliminate tire rub on the trail arm (5mm to 10mm). I checked my suspension travel without the spring on the car and my tire should still clear my fender lip. Especially with stiffer springs. Makes my rear track 10mm wider as a bonus.

- Add 50lbs to the rear passenger corner. Needed for class min weight and allows me to rebalance the car for a better setup.
- I'll be able to reduce my bite from 40lbs to 0lbs for even weight on the rear drive wheels
- It'll shift 1% more of my weight to the rear end for added traction (42% front / 58% rear).
- My Left/Right balance will improve 1% (50.5% L / 49.5% R)
- I'll be able to level the car more since the passenger side currently sits 0.75" higher for cross balance. Will look better, lower the car slightly, and should improve my roll center.

I've finished swapping the Group N bushing in on the passenger side arms. I have 1 more bushing to press in on the driver side arms and then I can reassemble. The trail arms are a pain. 1 bushing has a metal sleeve that I had to cut out, but luckily my bushing tool was strong enough to press the new one in. The other trail bushing is in the knuckle and there's very little room to work with (I'm doing this without taking the knuckle off the car). On top of that, the Group N bushing is so much stiffer and oversized by ~4mm that it's a really tight squeeze to get it back in the knuckle. I had to preload the bushing into a sleeve ~2mm smaller, and then press it into the knuckle from there for the last ~2mm of compression.

208660 208657 208658 208659 208661

mcamera

01-08-2025, 10:02 AM

https://youtu.be/Z9W5WCR5Nh0

mcamera

01-15-2025, 07:12 PM

After a little more research, several sources are saying to not place ballast weight far from the car's center of gravity to balance corner weights. So my idea to add 50lbs close to my passenger rear wheel doesn't sound like a good idea even though it would make the numbers look good on the scales. The analogy I've seen is having 500lbs on one side of a teeter totter. You can put 500lbs on the other side to balance it, but each side will be difficult to move and harder to stop once it is moving. There's a lot of momentum so the car will not transfer weight quickly during turns.

I can still put my weight low in the car to lower the center of gravity but I'm not sure how to get more weight on the passenger rear wheel without jacking that corner up 1" higher than the driver side (already 0.75" higher) or putting weight near it. Maybe put the weight near my center of gravity but slightly to the passenger side as a compromise? Back to the teeter totter analogy, I think adding a counterweight to the light side but near the fulcrum would help things move more easily in both directions. Without creating a 2nd slow reacting side. Does that make sense to anybody else?

Also ordered my dual adjustable QA1 dampers. They'll be here in 3 weeks!

J R Jones

01-15-2025, 09:39 PM

Add weight? How about reposition weight? Like move the battery.
I have not seen your corner weights. You can add weight to the RR by jacking up the LF. Of course you do not want to create a miss-match LF to RF.
You could unload the RF and LR. Or a mix of those suggestions.
The circumstance you are trying to correct is with driver weight in the car?
Unless you are loosing traction why strive to increase rear weight bias?
jim

Dave 53

01-16-2025, 01:14 AM

It is possible to corner weight the car and keep the ride heights equal. It just takes time playing with it - at least when I did mine. Numerous iterations, I had perfect 50/50 and the heights were off. But, I eventually got 50.0/50.0 and corner ride heights within 1/8". I had half a tank of gas and 200 pounds of bricks in my driver's seat when I did it.

When I was racing go karts, we had to come in at a minimum weight and the skinny racers bolted on lead. When we worked on the karts, we'd lift them up onto a stand. The etiquette is you would just ask someone that was walking by to help lift the kart onto the stand. Everyone would avoid skinny Rob because he had 60 pounds of lead on his seat.

I had a 1999 BMW M Raodster. BMW proudly advertised it's 50/50 weight distribution. Those cars have 40 pounds of lead in the rear bumper.

FFRWRX

01-16-2025, 09:30 AM

It is possible to corner weight the car and keep the ride heights equal. It just takes time playing with it

I don't know much about corner weighting a car, but how is this possible? If you start with the corners equal height and the corner weights are off, how can you adjust things, have the corner weights correct, but end up where you started with the heights correct?

mcamera

01-16-2025, 10:47 AM

Here are a few pics with my corner weights and the problems I'm trying to improve by adding weight.

209213 209214 209215

Great suggestions to get me thinking. The battery is in a great center position for left-right balance, but you're right moving it more to the rear of the vehicle could help. I think the only place I could easily mount it is on the driver side of the engine bay to stay away from the exhaust. Which would make my balance even more left side heavy. I'm not sure what other items I could relocate to the passenger side. Almost everything on the car is symmetrical. I debated my coolant overflow bottle but that would also put it near the exhaust.

209212 209219

My LF is already heavier than my RF. Jacking up the LF will add weight more quickly to the LF than the RR. This could work for a few pounds though since my LF has the lowest ride height. It'll make my front wheels more uneven, but at the moment my front wheels are not my bottleneck for grip so it might be a decent trade off.

I don't want to unload the RF or LR. RF is already lighter than the LF. The LR is already near a 4" ride height which is my minimum for a street car.

Weights are with me in the driver seat.

I often spin 1 rear tire coming out of slow turns and in general my rear end loses grip before my front end. So I'm trying to improve rear grip by putting even loads on both tires and shifting weight to the rear bias. I'm at 57% rear bias, and I've read up to 60% is good for a mid engine car as it helps press the tires into the ground for more grip.

Dave,
I used ride height gauges during my corner balancing to help choose which corners could go lower or higher. I did my best to keep things in check, but by the end the only way I could reach 50% cross weight was by raising the passenger side of the car 0.75" higher than the driver side. I'm using a 10gal Boyd fuel tank that's symmetrical and adds even weight on the driver side and passenger side. If you're using the FF tank which is 18gal and larger on the passenger side, you may have some extra weight on the passenger side which helped you achieve balance easier? If the passenger side of the tank is 12gal vs 6gal on the driver side, that's an extra 6 gal (48lbs) on the passenger side, and it runs all the way out to the side frame (further from the center of gravity = more leverage). Just one idea...

I hope by the end of the karting season skinny Rob packed on some muscle from lifting that kart so much lol.

BMW marketing made sure they hit 50/50 no matter what it took!

J R Jones

01-16-2025, 11:28 AM

Thoughts on anti-roll bars. When you measure/balance weights, disconnect a link on each bar and adjust for no preload when you reattach the links.
If you have a rear bar, disconnect it (for oversteer).
The (Subaru rear) front ARB is pretty light. Hard to correct on the 818, shorter arms is an option. I adapted a heavier bar and location. I will not run a rear bar to start.
jim
I still can not load photos here. Not even small jpegs.

Dave 53

01-16-2025, 11:55 AM

Not saying I'm an expert. Just sharing what I did based on the various methods of research I've done and being stubborn.

My priority #1 was 50/50 cross weight.
#2 Level 4" ride height.

It took 30 minutes to get 50.0/50.0 cross weight. Then 6 hours to get 50.0/50.0 cross weight and level 4". I can't articulate exactly how I did it. Mostly, if I needed an adjustment, there are two ways to make it - lower something or raise something and I just kept strategically picking what to do. I recall at times lowering or raising all 4 corners together to establish a new baseline and starting all over again. Maybe try swapping springs left to right?

I haven't put any effort into adjusting left to right or front to rear weight. Nothing to work with other than battery placement - mine is up front.

It's interesting to see your weights compared to mine. I think my 6 speed is 85 pounds heavier than a 5 speed! I've also got a fairly heavy passenger seat.

The FFR gas tank is larger on passenger side by a couple of gallons. It's about 14 gallons full. I wish it was 18 gallons! Actually, I wish it was 16 gallons. I can get 3 20 minutes track sessions on a tank of gas at every track except Thunderhill East. It's the only track I get into 6th gear and can't quite get 3 sessions on a tank. I need to add 2 gallons before that 3rd session. Running out of gas on the track is a HUGE party foul!

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mcamera

01-16-2025, 01:55 PM

I only have a front roll bar and I disconnected it during corner balancing. Then adjusted it for zero preload when I reattached it. Thanks for checking though as that can easily be forgotten. I can reduce oversteer by increasing my front tire pressures too, but I'm trying to add grip to the rear instead of reduce grip at the front if possible. It's not a lot of oversteer I'm playing with. I would like more rear grip for my launch and coming out of slow corners though.

Sounds like we had a similar method to corner balancing. Took me half a day too. I started off at a 4.5" ride height and would review my weights and heights with every adjustment. Carefully picking which corners to raise or lower so I didn't go below 4" at any corner. I got to 50/50 cross weights but my driver side is near 4" and the passenger rear damper was maxed out for height adjustability at 4.75".

I agree with FFRWRX. You have to make a change to get a change right? My weights at an even 4.5" ride height were TERRIBLE. My cross was 57%, my rear tires were 200lbs different, my fronts were 130lbs different. I linked my video to the spot where I talk about it. I had to shift a lot of weight to get a 50% cross.

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https://youtu.be/w_brzs9bPIY?si=8LCzduvK9V0cz_X9&t=180

I believe what you're saying I'm just not sure why we're seeing such different results. My driver side is also near a 4" ride height so I don't think your lower ride height is reducing the effects of anything by that much. I'm only 165lbs too, you mentioned you used 200lbs in the driver seat during balancing. You should have more driver side weight to overcome (31lbs based on your scale pic).

J R Jones

01-16-2025, 02:15 PM

A detail to consider is the influence or rubber/urethane bushings in (rotational) tension or compression which results in adding or reducing spring rate.
My rear suspension is/was all rod ends that do not bind.
Installing 2006 STI alloy front LCA was an education. The chassis mount holes were not close to fitting and had to be reworked in order to slide the fasteners in without binding.
I tightened the fasteners with the suspension drooping, I expect at ride height the joint isolation adds to the spring rate.
jim

Dave 53

01-16-2025, 06:35 PM

The goal of corner weighting is to get the front to rear weight bias of each side equal regardless of the absolute weight of each side. We both did that. Maybe a difference in ride height is mostly just aesthetic.

You're 69 pounds heavier on the left to my 68 pounds. If our in-seat weights (200 v. 165) were closer to each other, I'd say all is well with the world. How am I 35 pounds heavier than you, but my left cars is 1 pounds lighter? I have a light driver's seat and a heavy passenger seat, but by only a handful of pounds. And as you pointed out, more gas on the right which would explain some of it, but not enough to make up for my extra body weight. Curious....

Front to rear, you're 43.0/57.0 to my 40.8/59.2. My greater rear weight bias is easily explained by my much heavier 6 speed (I'm assuming you have a 5 speed).

If you need to add 50 pounds for your racing class, put it between your passenger seat and the door. Then re-corner weight the car with the ballast in place. You will have the best weight balanced car at the events!

mcamera

01-17-2025, 07:57 AM

Jim I also did the aluminum front control arms last winter and I rebalanced after I installed them. It only moved my cross weight by a few pounds. I made sure to tighten those bushings at ride height. I'll make sure to do all my balancing before I fully tighten my rear suspension this winter since I'm replacing springs, dampers, and bushings on the rear. Maybe that will help keep the rear bushings from adding force.

Dave, yes I have a 5 speed. Both my seats are racing seats, but not bare bones like a Kirkey seat. About half the weight of the OEM Subaru seats. Our weight comparison is strange. I wonder if the scales not being level could throw things off this much. I've corner weighted my car twice and both times were consistent when I put them on the scales.

Putting the weight by my passenger door circles back to my original question/concern. Longacre and Speedway Motors both say to not put ballast far from the center of gravity. They say it will look great on the scale, but make it harder for your car to transfer weight since it's so far away from the center of gravity (the point the car rotates its weight around). But I don't think putting ballast at my center of gravity will improve my left/right or front/rear weight distribution. I should be able to put it below my center of gravity which will lower my center of gravity though. That's all I can think of doing to make the weight useful.

Also I think Google was spying on us. YouTube started suggesting a bunch of corner weight videos. I watched one from DS3shooter that explained when you raise 1 corner to increase weight, you should also lower the opposite corner to maintain your ride height. And vice versa. I did not follow this method. I linked to the video at the point where he explains it.

https://youtu.be/yssSSfubGE8?si=pF1zii_KWSQ6-gcq&t=276

Dave 53

01-17-2025, 11:17 AM

Assuming a track with left and right turns, if my car is 69 pounds heavy on the left and I get 50 pounds to play with, I'm putting it all the way to the right! The goal of ballast placement is to MOVE the center of mass. The ballast isn't acting about the center of mass- it's MOVING the center of mass.

I recall the crazy forum debates we had about that weight in the BMW M Roadster rear bumper.

RPGs818SNA

01-17-2025, 12:18 PM

J R Jones

01-17-2025, 01:41 PM

Academic question: Adding weight far from the center of mass moves the center of mass some toward that added weight, but placement has no effect on the force needed for acceleration in a straight line. However, adding weight away from the center of mass increases the moment of inertia or rotational inertia. Depending on placement, it makes the car harder to turn (or stop turning), harder to roll, or harder to raise or lower the front during acceleration or braking. Is this effect noticeable in a racing environment?

Curious,
RPG

A sructured lab test would employ the scientific method to get your answer. A drag race would get you an answer.
A road racing course, (to a lesser extent an autocross) would result in a nebulous answer. What you gain in one dynamic you may loose to the opposite dynamic.
In our last roadracing endeavor we set the car up for each track. More and/or more significant right turns were prioritzied over left turns, or vice versa.
A track with significant straight would be set up for less drag and top speed. Aero and chassis were adjusted appropriately. Data recording helped evaluate each segment of the track. Lap time is less precise as it averages change.
We were using our strengths and the environment to our advantage.
jim

driveslikejehu

01-17-2025, 03:50 PM

The results on my R are similar to yours. In fact, your first posts about it were very instructive. Where I ended up, with all ride heights within a .25" plane.
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I think once you get this close, its diminishing returns relative to what I'm going to experience on the track. But that's just where I'm at, which is no expert. I've driven many track days, but not in an adjustable car.
And like you I have plenty of front bite and loose rear under power. So I'm adding a wing over the winter, mostly for fun.
The knowledge required to truly "dial it in" is harder to come by than spending money on parts, lol.

If I had to add weight, I think I'd bolt it on outside the passenger seat, to balance the driver placement. I'm pretty sure the moment of inertia doesn't know if you have a big weight in the driver's seat, or smaller weight outboard.

Thanks for sharing your development. It's useful/enjoyable to see someone else actively doing it.

Dave 53

01-18-2025, 05:33 PM

Academic question: Adding weight far from the center of mass moves the center of mass some toward that added weight, but placement has no effect on the force needed for acceleration in a straight line. However, adding weight away from the center of mass increases the moment of inertia or rotational inertia. Depending on placement, it makes the car harder to turn (or stop turning), harder to roll, or harder to raise or lower the front during acceleration or braking. Is this effect noticeable in a racing environment?

Curious,
RPG

Google says a 6 speed transmission is about 65 pounds heavier than a 5 speed. I also got heavier Driveshaft Shop axles. After switching to the 6 speed and new axles, I didn't notice any significant change in handling. But, there are factors to consider other than just the addition of 65 pounds to the rear of the car. A 200 pound passenger... I can absolutely feel that!

mcamera

01-21-2025, 04:18 PM

Dave, your comments resonated with me. Ballast is used to move the center of gravity, but the ballast weight also reacts around that center of gravity. Both are true. However, I think you've pointed me down the more important path. If I mount 50lbs of ballast by the passenger door, sure it isn't ideal for the forces acting on that 50lbs, but it moves the center of gravity to a better position for the other 2,280lbs in my car. That sounds like a good tradeoff to me. I've also driven with 180# passengers in my car and it didn't trash my handling or times. So I think it can handle 50lbs of well placed ballast. I'm going to avoid putting the weight near a corner though like I originally planned, and put it near the passenger door. That's at least good for the center of gravity axis that runs across the car.

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driveslikejehu, I'm glad you found some of my info useful! Your car does have really similar corner weights to mine but with more consistent ride heights. I agree there are some diminishing returns but keeping your tires in their optimal working range is so important. If I can get the rear tires loaded evenly for launching / exiting corners, and the front tires loaded evenly for consistent turning, it's going to pay off. Making one tire work harder than the other will limit my potential grip. Just trying to make every change for the better! I'll have to check out your wing when you're done.

mcamera

01-23-2025, 11:49 AM

As I'm installing my new dampers and springs, I'm realizing how poorly sized the FFR dampers and springs were. The old Koni's only have 2.5" of total travel and at ride height I was not in the middle of this range. There's very little extension possible before the dampers reach max length.

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They're especially bad at the rear. I thought the suspension would bind close to where the damper was fully extended, but that's not the case. The damper could only extend about 1" before maxing out and limiting suspension travel. My car never got on 3 wheels during racing, but it hopped across long sweepers and during heavy leaning. I think my inside tire was touching the ground but had almost not weight on it, so it would skip across the asphalt instead of being pressed down far enough to grip well. My stiffer 500lb springs will help reduce that roll but 1" of damper extension is still not enough. This is an unexpected bottleneck that I'm glad I found and I think it will be a huge improvement for my rear grip.

My new QA1 dampers (part number DD501) are a similar size but have 5.25" of total travel. Twice the Koni's. I also had the benefit of measuring my suspension at ride height on my old Koni's, so I could choose a new damper that would be in the middle of it's range at ride height. So equal compression and extension. These are going to do such a better job of keeping the tires pressed into the pavement across a wider range of suspension travel. I'm glad I didn't take the cheap route and just put stiffer springs on the old Koni's.

The extra travel and stiffer spring does mean the spring comes unseated at high extension as shown in this pic. So I got 4" helper springs and adapters to keep the spring engaged across the new wider range on the rears. The front suspension doesn't extend as far and from my measurements should keep the spring engaged across it's range. I'll need to confirm that once I get everything set at ride height and corner balanced but it looks like helper springs aren't needed on the front.

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Thought I'd share some of my progress. I'm finding all of this really interesting and seeing more benefits than I originally expected for upgrading the dampers.

Dave 53

01-23-2025, 12:11 PM

I'm looking forward to your impressions of the new shocks.

Spring rates will also affect where in the ride height adjustment you end up. When I switched to the heavier 6 speed transmission, the extra weight lowered the car. I maxed out the ride height adjustment on the rear shocks trying to raise it back up. The solution was stiffer springs. It seems springs that are too stiff might have the opposite effect - inability to lower the car.

If you have an open diff, I would diagnose your spinning of the inside tire as 98% open diff, 2% some other factor. I solved the problem with a Quaife QDH3Y LSD. I think it's the best option for a street / track car. Not 100% sure, but I think all WRX 5 speeds came with an open diff. STi came with a LSD.

mcamera

01-23-2025, 02:20 PM

Correct, my stiffer rear springs should move the spring perch down 1" to maintain my current ride height. This will keep me in the middle of the damper's range at ride height. It just requires a helper spring for large extensions of the damper where my main spring fully decompresses and would leave the spring seat.

I didn't have clearance to go from an 8" spring to a longer 10" spring to help with this, since the 10" spring would move the spring perch down another 2". It would interfere with my hub and I wouldn't be able to lower my car at all since the spring would be at the bottom of the height adjustment.

You're also right that it'll reduce how much you can lower the car. From my measurements I should still have no problem going down to a 4" ride height which is the lowest I'd want for a car I drive on the street. I'll be aiming for a 4.5" ride height.

If somehow these changes did force me to move away from the center of the damper travel though, I'd rather shift 1" of travel on a damper that can move 5.25" (QA1) than shift 1" on a damper than can only move 2.5" (Koni). A lot more options for tuning.

I have an open diff with my 5 speed and I agree. I'll look at an LSD whenever I need to change my clutch. I have no clue how old mine is. Thought I should fix the soft rear suspension that's bouncing off of bump stops and making my tires rub on other parts first. Using ballast to get even weights on my rear tires was one way I thought I could improve my rear power distribution without going to an LSD yet. Trying to make the most of what I have.

mcamera

02-03-2025, 10:01 AM

https://youtu.be/BsVxSkvJt4A

mcamera

02-10-2025, 11:25 AM

I did some corner balancing this weekend and discovered a few things. I set my ride height to 4.5" +/- 1mm at all corners and my corner weights were terrible. 37/63 for my cross.

I balanced my car last year with a 1/2 tank of gas which worked with my old summer tires, but with my new stickier tires and improved setup that now starves my fuel pump on longer turns. So I've been racing with a 3/4 tank of gas and I actually only need 25lbs of lead weight to meet my class minimum weight (2330lbs). I put the weight under my passenger seat and started balancing the car.

I found that disconnecting one end of the front sway bar wasn't enough. My front wheels have more travel with my new dampers and the bar was interfering with my upper control arms and springs, so I removed the sway bar and all its hardware. About 6lbs of gear. Once again, the FFR Koni damper had a really short travel so the sway bar worked ok with that setup. I need to double check if I need helper springs on the front dampers now.

210332

I got everything balanced to 50/50 cross weights and was able to keep my ride heights a little more level than my previous setup, but my passenger side still rides 1/2" higher. Part of this improvement might be due to the stiffer rear springs that don't compress as much. My starting ride height was 117mm and here's where I ended:

LF/RF - 110mm / 121mm (+11mm)
LR/RR - 112mm / 123mm (+11mm)

Today's progress
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So did I improve everything that I wanted to? Do I have zero bite on my front and rear wheels, did I get 50/50 L/R balance, shift 1% more weight to the rear? Nope. My estimates were with adding 50lbs of lead and I only need 25lbs now. Even though we'll spend $1000's to remove 25lbs from a car... it doesn't make that big a difference. Here are my big improvements:

Before / After
Front bite: 36lbs / 36lbs
Rear bite: 36lbs / 34lbs (-2lbs)
Right %: 48.43% / 48.49% (+0.06%)
Rear %: 57.12% / 57.33% (+0.21%)
Passenger ride height: 0.75" higher / 0.5" higher (-0.25")

Last season vs this season
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That being said, my setup is better.
- The fact that my weight distribution didn't change dramatically means I added my weight close to the center of gravity which is ideal. And the weight is on the floor of the car which is below the center of gravity, therefore it'll lower the center of gravity. Probably negligible but I didn't make it worse!
- I also added 34lbs to the rear wheels and only 16lbs to the front wheels. I wanted to shift more weight to the rear.
- Removing the front sway bar was also really important to give the new front dampers their full range of motion.
- The car is more level. Not only does it look better, but the suspension is in a more similar point of its travel on LH vs RH sides. I was running slightly more camber on the RR tire last year because it was 0.75" lower in it's range than the driver's side. They're closer now.

J R Jones

02-10-2025, 11:57 AM

mcam, You threw me off with the 170mm ride height typo.
I do not know what you are referring to with "Front bite" and "Rear bite". That is measured how?
The Subaru rear A/R bar on the front is terrible. I removed all that and have a similar diameter bar from my Acura donor mounted on top of the lower frame tubes behind the battery. No interference.
As usual my photos do not load.
jim

mcamera

02-10-2025, 01:24 PM

J R Jones

02-10-2025, 04:32 PM

Yeah sorry about that, I corrected the post. Easier to measure heights with the car on the scales while you're corner balancing. Scales were adding an extra 60mm.

Bite is the difference between wheels on the same axle. My rear bite is 34, so my LR wheel has 34lbs more than the RR wheel. Ideally I want 0 bite (same weight on both wheels).

The Subaru bar had a very limited range to move with the FFR Koni's but it worked. Mine always had scrape marks on it from interfering with the upper control arms.

Ahh, AKA Static Bite.
FWIW I created my first album and I am surprised to see all the photos I have loaded previously are in there. As an avid editior I determined some of those photos are now irrelevant but they can not be deleted.
I do not like that.
Starting an album was an experiment to load new photos to see if I could attach them to this thread. I cannot load photos to my album (or threads) and it is within recommended dimensions. Persona non grata.
jim

mcamera

02-11-2025, 10:49 AM

I always have an issue with quick replies. I have to click "go advanced" below and then I can attach my photos with the "insert image" button at the top near the font settings.

J R Jones

02-11-2025, 11:22 AM

mcam,
At your suggestion, this reply attempts to load my ARB photo.
Nope. Same fail to upload.
Shame, I would have also loaded a picture of an Acura V6 in my 818 chassis.
Given the (lack of) Subaru powertrain restraint with FFR mounts, I use the complete Acura mount system.
The Acura aluminum subframe mounts to the frame with six isolators.
The Acura powertrain mounts to the subframe with two isolators and to the frame with three isolators. Yeah, it is complicated.
jim

mcamera

02-13-2025, 09:21 AM

Took a look this morning and my front springs do come unseated by about 1/2" at full droop. Ordered another set of helper springs for my front shocks. So I'll have them on all 4 corners now. I'll have to fix the corner weights again on the front wheels once they're installed, but should effectively just move my spring perch down ~1/2" from where they're at right now. Helper spring is 0.44" fully compressed + the adapter that connects it to the main spring.

mcamera

03-04-2025, 11:38 AM

Added helper springs and rebalanced my front shocks. Here's my final corner balance. Slight improvements all around compared to last year, but with a more appropriate rear spring rate and properly sized dampers (twice the travel and in the middle of it's travel at ride height). Still waiting on hardware to bolt down the 25lb brick of lead under my passenger seat. I also torqued down all my suspension bushings at ride height which is something I didn't do properly when assembling the car. I had used a jack to raise the wheel some, but not exactly at ride height.

211113

I'm excited to take a test drive and start adjusting my dampers, but it's been too cold here. Recommended to not put weight on 200 tires below 20F or the compound irreversibly cracks. And if they do get below 20F, you have to get them above 40F for at least 24 hours before using them. I've been careful all winter to keep the car on stands. Should get a chance to drive within a couple weeks as things are warming up. The tires don't stick below 60F so it's not like I could push the car anyways, but it would be good to find any issues now. Points races start 4/13!

driveslikejehu

03-06-2025, 09:26 AM

Can you remind me where you ended up with spring rates? Did you start with 350F, 275R?
Also, I think you’re using driver weight when you corner balance?
Our weights are similar; 2325# for my R with me in it, tho I’m about 20# heavier than you. I thought the coupe might be heavier but I guess the R is similar with all the steel in it.

I found a forum post from Jim at FFR recommending the setup for a non-aero R as similar to the S but “probably 50# stiffer.” So I built my R with 400F/300R.

The S spring plan never really made sense to me though I respect that FFR did the right analysis and testing. My Cayman, and other mid-engined cars I researched, have heavier rear springs. So partway thru track season last year I swapped front and rear springs (300F/ 400R) and I have a splitter. Got a good corner balance as before and feels about the same on the track.

Now I’ve added a rear wing so may go to 500# rears as in the planned R setup.

Thanks for sharing your development work. I don’t know if I could tell the difference in damping rates, but maybe as I get more used to the car.

Hobby Racer

03-06-2025, 01:17 PM

As another data point. I run 500# fronts and 700# rears on my R. I have quite a bit of down force and run on smooth high speed tracks mostly. I've been tracking the car since about 2018 so I have a lot of seat time in it.

mcamera

03-10-2025, 11:33 AM

I started with the FFR 350 front / 275 rear. Added 25lbs of lead under my passenger seat to get to 2330lbs (minimum weight for my autocross class). Corner balanced with me in the car (165lbs). My springs are now 350 front / 500 rear.

I read through a lot of posts from FFR and members (thank you everybody that's shared) regarding spring rates and here's what I concluded.

- The FFR springs were chosen as a compromise for the street (350 Front / 275 Rear). This is not a hardcore, optimized for racing setup.
- It's softer in the back (275lb) because the shock mounts further out on the arm (less leverage) than the front shocks which mount further in on the arm (more leverage means you need a stronger spring for the same effect).
- If you're building a track car or adding aero, you can swap the springs (275 front / 350 rear) because you need a stronger spring in the back to help with the added downforce
- Wayne ran 500 front / 600 rear on slicks w/ full aero. A member tried this and said it was too much for a car on street tires, so he backed off to 425 front / 500 rear.
- Bob eliminated his body roll by only upgrading the rears to 500lbs. No change to the front.
- Sixstar had good results with 350 front / 550 rear

To bring it all together, I used a dynamics calculator to find the appropriate spring rates based on my suspension geometry and it came out just under 350lbs for the front and 500lbs for the rear. Stiffer isn't always better. There's a sweet spot where your wheels react quickly to bumps but softly enough that your tire stays pressed into the ground. If your car hops over every bump you're taking weight off the tires and losing grip. Here's the calculator I used. This site also has a lot of great info.

https://farnorthracing.com/autocross_secrets16.html

My own speculation after upgrading my dampers/springs this winter is that there's a cost/design portion to this equation also. The rear suspension has a longer travel than the front. When you combine the yellow Koni's which have a short travel and a softer 275lb spring which compresses quite a bit at ride height, you can use the whole range of travel. If you put a 500lb spring on the koni, it doesn't compress much at ride height so the spring can unseat when you hit a dip in the road (you need a helper spring). If you upgrade to a damper with longer travel, once again the spring can unseat (you need a helper spring). I think FFR used a shorter damper + a softer spring, so the package was simpler, cheaper, and kept the spring safely seated. Even though it comes with lots of other compromises.

driveslikejehu

03-10-2025, 01:24 PM

Thanks for the info...
I can't remember if you mentioned "vsusp.com". Another site to calc suspension geometry, etc.
My first calcs didn't show dramatically different front and rear wheel rates; maybe 1.5:1 rear and 1.7:1 front, but I haven't confirmed these.
A little warmer today here in Chicago, so only 2 months till track time, lol.

mcamera

03-11-2025, 08:12 AM

Lol I feel ya. I finally drove my car for the first time Sunday. Getting some days in the 60's now down in Kentucky. I haven't used vsusp but I've heard it mentioned.

Been playing with my damper settings but I need more seat time to figure it out. Pretty fun to play with but I'm going to drive myself crazy looking for perfection haha. My dampers have 18 settings for compression and 18 settings for rebound. 0 is soft, 18 is hard.

0C/0R - very comfortable, floaty ride

8C/0R - firmer over bumps, but bouncy

12C/6R - close to a good firmness, slow bouncing turns into smaller/quicker bounces, kind of like driving on a brick road

10C/10C - best so far, caught myself going 15mph over on the highway because the car felt so well planted. Not sure if good for street driving will mean good for autocross but this would be a nice starting point.

Rebound is interesting. At 0, the wheels rebound the fastest so it makes the car feel bouncy because the damper extends too quickly/strongly. Turning that up to 10 (should have gone to 11 for Spinal Tap) slows down how quickly the damper extends, which let's the car "fall" over bumps more firmly. Makes the car feel more confident in what it's doing even though you're slowing down the wheels' reaction time.

driveslikejehu

03-11-2025, 09:30 AM

As always, sharing your development is appreciated; interesting and informative
The only time I've messed with damping adjustments was on motorcycles back in the day. Too much rebound and we'd see what we called "jacking it down." Couldn't rebound fast enough before the next bump, so you ended up compressed almost onto the bump stop.
Next time I pass thru on the way to NCM MSP I'll ping you...

mcamera

03-11-2025, 03:59 PM

mcamera

03-18-2025, 07:30 AM

I was test driving my car and changing damper settings last night. I pulled off into a parking lot to change the settings and when I started pulling away something in the back of my car was squealing and grinding. I was guessing my parking brake shoe had fallen apart because it sounded like it was coming from my rear driver hub.

Got home and lifted the car up. The rear driver wheel spun smoothly and quietly. The rear passenger wheel was grinding when I spun it by hand. Took off my rotor and this small rock fell out with a tiny chunk of copper metal which I'm assuming was part of the brake shoe. I think the rock chipped off a little brake pad at the end of the shoe. Put it back together and it spun quietly but my kid was asleep in the room next to the garage so I couldn't take the car out for a drive to confirm. Strange that the rock got stuck in there for a couple miles but couldn't find its way out. At least it was an easy fix.

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lpmagruder

03-18-2025, 08:21 AM

There should be a little rubber cap on the hole for the parking brake adjustment mechanism. If yours is missing maybe it got in there?

On a similar note I have a bunch of points in my car where little rocks that size gather, notably around the battery tray and under the doors. I've been meaning to go through and make some new panels to keep them out. If I don't vacuum them out every 1000 miles or so you can start to hear them sloshing around when turning or braking ��

mcamera

03-18-2025, 12:42 PM

I did notice a dime sized hole in the backing plate. Maybe the cap fell out recently. The front engine bay collects a ton of rocks on my car too. Didn't notice it much the first year on the road. I think sticky tires and autocrossing kicks up lots of junk. The parking lots we use always have a lot of rocks that get cleared off by the first heat.

mcamera

03-18-2025, 02:55 PM

Also worth mentioning some of my damper testing last night. Most adjustable damper manufacturers recommend this method for finding your baseline settings:

Set compression and rebound to 0
Only increase compression until the ride gets rough, and then back off 2 clicks
Only increase rebound until the ride gets rough, and then back off 2 clicks

I was up to 14/18 on compression yesterday before my brake problem and the car was still surprisingly compliant. A little stiffer at 20mph than 60mph but I'll try 16 clicks next time. I didn't think I would need to go this high but maybe the last few settings will get stiffer, faster (non-linear). I'm having fun understanding all of this.

mcamera

03-19-2025, 07:31 AM

Drove around some more last night. I found 14 for compression pretty good. 16 was a little too stiff/jumpy for the street.

Then I only needed 4 for rebound to get rid of the bouncing. 8 was definitely too stiff, and 2 still had some slight bouncing.

mcamera

03-24-2025, 09:18 AM

Had some good weather this weekend to dial in my dampers. Here are my notes:

Using the manufacturer's tuning method of set comp first, then rebound (I have 18 settings for each knob):

- Compression 14 (16 was too stiff)
- Rebound
- 2 was bouncy
- 4 was good and compliant
- 6 turn in is noticeably sharper but too stiff
- 8 too stiff
- Result was C14-R4

Like I mentioned above, 6 on the rebound had such a better turn in that I wanted to try a softer compression to see if I could keep the higher rebound. So I tuned more from there.

- Lower comp to 12 (C12-R4). Too stiff. Even though R4 worked before, it was now too stiff. There's some ratio that works best for each comp/rebound setting.
- Lower rebound to 2 (C12-R2). Bouncy. Not achieving my goal of raising rebound.

- Lower comp further to 10, put rebound back at 6 (C10-R6). Great compliance, turn in is not quite as sharp as the old C14-R6 setting.
- Raise rebound to 8 (C10-R8). Too stiff.
- Lower rebound to 7 (C10-R7). Great compliance, sharper than the rebound 6 setting, not quite as sharp as the old C14-R6 setting.

Final settings, compression 10, rebound 7. Feels like the suspension has a wider window to work and is a better all around setup than the C14-R4 setting. My opinion might change if I have too much body roll or hopping during autocross, but this is a great aggressive street setup to try first. Trying to error on the softer side since I already put stiffer springs on the rear.

Also had a chance to start painting my wheel wells. I put this off for a couple years but it's time to make the car look more finished. Using flex seal liquid to paint a rubber coating. Cheap, UV resistant, and hopefully a rubber coating will damp the sounds of a few rocks.

Cleaned/scuffed the panels with sandpaper
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1st vs 2nd coat. A small foam roller was way less messy than a brush. This stuff is very runny but self levels well. Just used a brush for edges.
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Looks much better
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mcamera

04-14-2025, 02:18 PM

https://youtu.be/H3WIBlYiWFw

Dave 53

04-15-2025, 01:56 PM

Great video production!

I also thought the sway bar was interfering with my suspension. But, when I took the coil overs out and exercised the suspension to full travel, with all the parts moving together, there were no sway bar clearance issues. Looking forward to your handling impressions with no sway bar. At the same time (exercising the suspension), it was a good time to check bump steer. I was able to fine tune the steering linkage washers to effectively eliminate bump steer. The two pictures are the "before" pictures. Note the ruler height measurement and position of the top lug relative to the ruler. In the "after" pictures, after adjusting the washer stack, the position of the lug relative to the ruler is the same both up and down.

Maybe you're already doing this... I lowered the car onto the scales with 4 layers of contractor plastic garbage bags between the scale and tire to reduce any binding. Don't give up on getting the ride height even! But, I also get that last 5% can take 90% of the time.

Also looking forward to your feedback on those shocks. I'm still on my Koni yellows. What are the QA1 part numbers?

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mcamera

04-18-2025, 08:02 AM

Thanks Dave! I was trying to adjust the sway bar with the car sitting at ride height, and it would always hit 1 of the control arms. When I raised the car with the bar disconnected I realized my damper extended another 1" so the bar had been holding up the suspension. Since taking it off, my steering is also significantly easier. Things were definitely interfering and binding on my car. Maybe my STi lower control arms made it worse? With stiffer springs and adjustable dampers to control my body roll, I don't think the skinny OEM bar would be doing much work anyways.

I maxed out the washers on my Baer bump steer kit. I still have some small bump steer over large bumps but it's not bad.

I bounce each corner of the car after adjusting my corner weights, and rock the car forward/backward while it's in gear to unbind everything. I just got an alignment and did some corner weight touchup afterwards. I did get down to just a 5mm difference between all wheels!

However, after my alignment the car was squirming side to side so I was looking at the printout and they accidentally doubled the toe I asked for. I asked for total toe in to be 1/16" (0.15deg) in the front and 1/4" (0.58deg) in the rear. They gave me 1/4" per wheel in the rear, so 1/2" total toe in. Way too much toe. Just dropped the car off again this morning for them to fix it.

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Looking at my tires, they're all wearing more on the outside edge. My grip is rear limited so I'm focusing on those. -2.5deg camber gave me the best results last year. I tried more camber but it made my car hard to launch and I'd spin a wheel coming out of turns, so I don't want to increase camber. Hoping the stiffer springs/bushings keep the tire from rolling onto the outside edge so much. I'm starting at -2deg camber this year and figure I'll go +/- 0.5deg after I see how it's working at my first race.

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I'm using the DD501 QA1 dampers. Recommended for a ride height of 14-15" (distance between mounting bolts at ride height). I measured an average of 14.5" between the bolts on my Koni's and confirmed with QA1 that these would be a good fit. I ended up having to put helper springs at all corners because the QA1's have more travel than the Koni's. First race is 4/27 so we'll see how they do!

https://qa1.net/products/proma-star-coilover-shock-double-adjustable-11-5-8in-to-16-7-8in/

mcamera

04-18-2025, 09:35 AM

Just got my car back and it drives well again! Now I know what a 1/2" of total rear toe in feels like and you don't want it haha. Lots of side to side wiggling when driving in a straight line. I'm at 1/4" now and the car drives great.

Dave 53

04-18-2025, 10:19 PM

I've been liking just a little (0.04 degrees) toe OUT in the front and just a bit more (0.07) toe in in the rear. Turn in is amazing. In theory, the toe out should make the car a bit unstable going straight, but I'm not feeling it street driving or on 120 mph track straights.

mcamera

04-21-2025, 08:04 AM

That's a really small amount of toe on each (1/64" and 1/32") so I'm not surprised you don't have any negative effects. For all intents and purposes I would call that zero toe. FFR recommends 1/4" toe in on the rear so the car doesn't toe out under compression and cause snap oversteer. I ran 1/8" last year and did have some oversteer moments so thought I'd try a little more. They said it makes the car a lot more fun to drive which is probably true if you're not flipping back and forth between toe in and toe out during a turn. Here's my final alignment.

Camber
FR –1deg
RR –2deg

Caster
FR +5.1deg (avg)

Total Toe
Front IN (1/16”) or 0.15deg
Rear IN (1/4”) or 0.58deg

It did knock my corner weights off by 2% which is more than I expected so I touched those up again. I got all of my ride heights within 3mm too.

Before/After
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A little shared learning for anybody that has had trouble with uneven ride heights like me. If you have a corner weight that is really low, and you increase the height at that wheel to add weight, majority of the weight is added to that wheel, and only a little to the opposite corner. But when you're near a 50% cross weight, adding height to that wheel adds the same amount of weight to the opposite corner. This only happens right near a 50% cross weight though. This means if you get to a 50% cross weight and one corner still has a high ride height, you can lower it, and increase the height at the opposite corner. It'll shift weight 1:1 and give you the same balance but improve your ride heights. We're talking small 1/8 turns of the height collars because adjustments get more sensitive near a 50% cross weight.

mcamera

04-28-2025, 11:53 AM

Autocross went well yesterday. I was getting used to my new setup and finished 24/69. Not an amazing result but what I expected for my first event. It was in the 50's so I struggled getting my Falkens up to temp. Everybody else runs RE71's. It also seemed like an oddly strong field. My place wasn't super high but the guys I compare myself to didn't pull away by much. 3 of the 4 guys in front of me in my class placed in the top 6... all heavily modified Miatas on 305 tires.

Anyways, not excuses. The car felt good. Definitely have room to improve but it was sharp without being bouncy, skipping, or hopping with my first attempt at damper settings. Turned out to be a great starting point. The rear wheels had some small spins as they fought for grip out of turns but very close to a good setting. The car tends to oversteer when pushed and I saved 1 spin. It does feel more on edge and likely to spin if pushed too hard, but I was getting used to where the new limit is.

I need to analyze my tires and chalk marks a little to choose what to do next. Not quite sure what to try to improve first but it looks like my rear tires would like some more camber.

mcamera

05-01-2025, 12:55 PM

Looking at my chalk lines and comparing that to my autocross feedback, the rear grip is still my weak link and needs improving. Just a refresher from last year's results:

- Gained 26 places when I switched from Kumho summer tires to my Falken RT660's
- Gained 8 more places when I optimized just my rear camber (-0.5deg to -2.5deg)
- Gained 21 more places optimizing my tire pressures (40psi to 30psi)

Crazy to see how much camber and tire pressure helped. Just as much as upgrading tires. I think my camber results are understated and it was actually very important in allowing the lower tire pressures to work as well as they did. So with that same thinking, I see an opportunity for some small changes to bring big results.

With decent camber, you would think that this part of the tire does the most work when accelerating in a straight line. Slightly leaning on the inside edge.
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Then during a hard turn, the tire rolls flat and the whole surface is being used (ideally)
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But I'm only seeing heavy wear on the outside of my tires. So much that it's a darker color and the surface is rougher than the rest of the tire.
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And the inside edge is seeing no wear
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Here are pictures of the outside and inside edges of my rear tire. At -2deg camber and 32psi I'm still using a lot more of the outside edge than the inside edge. The chalk shows how my stiffer springs haven't reduced how much the tire rolls onto its outside edge. So the first thing I want to do is increase camber to -3deg. This should shift some of the work (and wear) to the middle of the tire. Last year I tried -3.5deg and it hurt my straight line acceleration and lap times, but I'm still seeing a need for more camber. Maybe my stiffer springs and bushings will transfer weight better now and allow me to use more camber, because only 20% of my tire is being used to its limit. If this works well and shifts the wear away from the outside edge, I should be able to reduce my tire pressures a little further and improve my rear grip.
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My front tires don't need improving yet. They aren't my current bottleneck and are wearing more evenly.
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