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Old 05-27-2014, 08:02 AM   #1310
Doozer
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Quote:
Originally Posted by CSG Mike View Post
Pure setup.

Your static load balance is way off.

Assuming motion ratios of 0.95 front, and 0.75 rear, look at this ratio:

Front effective spring = 550
Rear effective spring = 500 * 0.75 = 375
Front effective spring % = 59.45
Rear effective spring % = 40.54

Keep in mind that motion ratio in the rear is probably lower than 0.75, so my numbers are off.

Now add the fact that you're adding MORE spring to the front with the front sway, and no rear sway, and you're overloading the fronts, causing the fronts to always wash out before the rears, short of a massive driving error or forcing the rear to come out.

Now, because you have this static understeer, you're trying to fix it by adding front toe-out, which helps initial turn-in, but hurts static grip, making the front understeer even more.

The rear toe-in, I'd guess, is to help stabilize the car, because any oversteer that occurs with your current setup is violent.

Proposed Solution:

Increase front camber to -3.4 on BOTH sides, and increase rear camber to -2.35. Your inside pyrometer readings are higher because you have too much toe.

Soften your front springs, or add rear springs, and re-connect that rear sway bar.

Then, zero out your toe, front and rear. The car will be "looser", but far more progressive. If it's too loose, then add 1/16" total toe-in. If it's still too loose for your taste, then add more rear camber.
Thanks Mike,

Greatly appreciated. We'll give it a shot and let you know the results. Next race will be mid June.

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Last edited by Doozer; 05-27-2014 at 08:24 AM.
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