My WCM S2k upgrade project.

[Grady]

Starting a project page for my new WCM. First thing I noticed was the ride and ride hight. Decided to update the shocks/springs. Opted for the QA1 double adjustable shocks. Ordered the 300lb springs for the back and the 400lb for the front as the kit instruction listed. These shocks are a larger body shock but looked like I could make them work. I was shooting for a 12 inch shock ride hight for the car. The car had a 12 inch in the front and 11 inch in the back. Once installing the shock I had to mount both front upside down to clear. The back I had to mount upside down and mount the upper mount inside the mount instead of between. But at that all cleared good. Setting up ride hight notice that there was spring slack at extension. Did some spring calculations and came back at 266lb spring for the front and 166 springs for the back. Ordered 220 springs for the back and going to move the 300lb springs to the front this should fix the spring slack issue. A couple of projects in the works are I have a new set of R888R tires for it. While I have the wheels off will get them powder coated black. Also have a more original exhaust setup to weld up. High flow cat, and a flow monster exhaust. I have a lot of other updates I want to do and will post them as this project continues. 

[Grady]

Ok starting some initial changes. First one is a better 3rd brake light. I live in Dallas and do not want to get rear ended. Have returned the headlight housings to stock and installed some upgraded LED headlights with built in turn signals. Upgrading the turn signals to daytime running lights. Will post those when done. Also have ordered some Lotus 7 style rear lights. Converting the turn signals to yellow since those have proven to reduce rear end accidents. 

 

 

 

 

[Grady]

Did not like the trailer brake light they had on the car. Bought the Catherham/Westfield style. I think these look a lot better, and with the amber turn signals you are less likely to be run into. I will have to run an additional wire since the turn and brake lights are separate now but that is not an issue. 

 

 

[nc7s4]

Much better!! here are some pictures of my WCM light upgrades.  Same thought process as you followed, pretty much

 

 

[charles5448]

On 8/28/2024 at 3:02 PM, nc7s4 said:

Much better!! here are some pictures of my WCM light upgrades.  Same thought process as you followed, pretty much

 

 

Are you running a front sway bar in your car? Also, what are your spring rates? Saw your video of the car on track and it looked super stable. My WCM feels loose when autocrossing. Looking to dial a bit of that out. 

 

-Charles

[nc7s4]

Not sure what my spring rates are but would love to find out.  I looked for markings on them but can't see anything.  No front roll bar.

[nc7s4]

I've sent qa1 an email to see if there is any way to identify these springs without taking it apart!

[MV8]

Measure the wire thickness with a common, 6 inch dial caliper and post what you find. It can be done without disassembly and the caliper is about $20 off ebay or harbor freight. I've used them side by side with $600 aviation calipers to compare accuracy.

[Grady]

I am not sure what spring rates were on mine. The manual calls out for 400 or 500# springs on the front. When I got mine it has a motorcycle type rear shock that rode terrible. It had a front sway bar that I took off. I took all the shocks off and replaced with new double adjustable QA1’a DD401’s with those I had to reduce spring rates a lot. I ended up with 220# rear, and 300# front. The fronts fit fine just installing upside down. The rears I had to install upside down and move to the inside of the upper mount to clear the driveshafts. 

Edited October 17, 2024 by Grady

[nc7s4]

2 hours ago, MV8 said:

Measure the wire thickness with a common, 6 inch dial caliper and post what you find. It can be done without disassembly and the caliper is about $20 off ebay or harbor freight. I've used them side by side with $600 aviation calipers to compare accuracy.

I measured 11mm

[MV8]

Best guess based on what I see, a typical inside diameter of 2.5 inches, and the rough measurement (probably 11.07mm wire), these are 250# per inch.

[nc7s4]

Same setup in the back. I guess you are probably pretty close either 250 or 300. I believe 300 was the baseline setup for a lot of these cars.  Some wcm people put heavier springs in the front, but the balance of the car is heavier in the rear.  So I would think if anything heavier springs would go in the rear.  I think the real solution is adding an anti-roll bar. 

 

Anti roll bars would be a fantastic add.

Edited October 17, 2024 by nc7s4

[charles5448]

My WCM has 225 rears and 450 fronts. I'm trying to dial out some liftoff oversteer while autocrossing. Not sure which direction to head with springs. (i.e. heavier or lighter rear, heavier or lighter front) Worth noting, when turning into a corner, it feels like I need to give the wheel input and it takes a moment for the car to react. I think this is due to the soft suspension on the car needing a moment to load up. 

Edited October 17, 2024 by charles5448

[nc7s4]

I've been looking at my springs a little bit more today and they are 1 7/8 inside diameter.  So I think they might be 150#  !!  Already have some calls into different places to get some heavier ones.  I think mine are waaay too light.

 

Thanks for asking I might not have investigated.  

 

I think your setup sounds pretty good- it's what others have had success with.

 

What diff are you running?  I have a line on a good deal for a WRX STI r180 which could be a huge upgrade.  I did it recently 

 

What's your rake?  My car started out with tons of rake and I leveled it out.  Now it's 15mm difference front to back.  Started like 40mm

 

That setup was causing mid turn, power off oversteer

[charles5448]

I have a r160 3.9 diff in the car right now. Going to end up running 15s to try and get some more gear. I can't reach VTEC in 2nd gear during most autocrosses with the 3.9. 

 

I've tried adjusting rake but not sure if I went far enough. The front is around 5.25" and the rear is around 5.5" 

[nc7s4]

Tire pressure in the back?  I run around 20psi. Toe in the back, camber?

[MV8]

At 1.875" id, the rate would be 500# per inch. That is not the wheel rate.

Edited October 17, 2024 by MV8

[nc7s4]

I ran some similar calcs based on the wire size and got that too.  However, looking at what qa1 sells in this size shows the lighter springs.  Mine sure look like these ones 

 

https://qa1.net/springs/1-7-8-inch-id/

[charles5448]

34 minutes ago, nc7s4 said:

Tire pressure in the back?  I run around 20psi. Toe in the back, camber?

Any chance you could share your alignment specs with me. I've been guessing since I put the car back together. 

 

[nc7s4]