Some friends and I rented Buttonwillow Raceway for a day in June. This is going to be cool! Some Porsches, A barely street legal NSX, a C5 and a couple BMW 5's, one being an M5.

I have the usual suspension modifications (Eibach ProKit,, CT sways, Illumina shocks). I am wondering what I should set the shocks at (1 being soft, 5 being extra firm) for the front and rears for a road course?

I am also considering a one time purchase for some DOT approved racing tires for the track if it is reasonable $$. Any suggestions? I just don't want to tear up my SO-3's!

TIA,
Steve

 

The NSX, 911, and M3 have had their suspensions setups debugged for a long time now. Not many people setup CLS for road courses (if any), so you'll probably have to go the "trial and error" route.

You basically will have to sort the car yourself

I think it's pretty cool that you'll be running on a road course tho'

 

Aginst the other cars, does the phrase "understeering pig" have meaning to you?
Dan

 

TopGum, when are you going? Could I tag along? See if they'll let a convertable C5 come w/ no roll cage!

 

Well Dan, yes. We are not racing, just out to have a good time. I'm the little guy for sure but I might surprise the rest with how quick the car can run with the S/C, headers, etc. Especially the BMW guys. I'm expecting to be owned in the turns by all but on the straight, well that might be a different story The NSX owner races with his club often and I''d like him to take me around to see what an experienced racer thinks.

My question is how to minimize the understeer. Do I just set the fronts to 5? Should I ask the shop to dial in some neg camber? I'll likey leave the back seat at home to make easy access for the rears.

CL Power, I'm not sure but I'll ask the guy who oraganized the event

 

Shock setting will not help O/S very much, set them full hard to start and increase front tire pressures. Since you have a S/C and have some power to spare you might want to try adding some weight to the trunk to move the weight bias towards the rear. Sacks of concrete work well for this. Have fun and keep the shiny side up!
Dan

 

i thought making the rear slightly stiffer then the front would induce oversteer thus compensating for some of the understeer.

 

damn, i'm jealous......... . wish my friends would rent out a track too so i could come and play.

Set up the car like at 4 in the rear and 3 up front. if ur still understeer try 5/3 and 5/4. be safe and have fun.

 

I like Buttonwillow and have some experience there.

This post is correct. The rear needs to be firmer relative to the front from stock settings. I'd start with both in the middle and tune from there. Which course are you running? There are 20+ layouts I have run there before in a Spec-racer and there is a combination of low speed low banking and high speed w/some banking corners (Talladega). Magic Mountain is a fun rising turn with a dropoff right at the apex. You have to be on throttle over the hill or the rear will snap on you. With some many corners any setup will be a compromise. Even with a good balanced setup, you will push in some corners and be loose in others.

You will probably want 35psi front and as high as you dare in the rear, otherwise, she wont rotate in the corners. My 280z likes 38 fr and 42 rr and it is rwd. Good luck and above all, have fun!

 

Sounds like an awesome time!

I wonder how poorly you'll handle the turns versus a 530 or whatever the non-M-5-series is gonna be. Let us know!


quote:
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Originally posted by 01 Cl-s
i thought making the rear slightly stiffer then the front would induce oversteer thus compensating for some of the understeer.
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This is accurate. Have fun tuning it!

 

Sounds like Race #2 or #3. Any suggestions on tires? Should I "run what I brung" or get something special for the occasion?

CL Power, shoot me a PM... looks promising.

 

hey video tape it i wanna see how our cl's handle the course