Road Race setup questions

[Catwood]

I've got adjustable height Konis on my 2000 GTS with rebound adjustment. I just had the car aligned, corner balanced and bump steer done.

Running at willowsprings last weekend I changed tires/rims. I have a smaller front 285 now vs 315. I was able to trim about 2 seconds off my previous best.

However, my car is pushing (understeering) alot....I mean...ALOT. I watched the incar video and you can hear the tires screaming at every corner. I had a hell of a time getting it to turn, especially on the faster corners.

So the question is what should I adjust...fronts or rears and do I go up or down?


Thanks,
Carl

 

[Irid]

Steady state understeer isn't shock related, it's roll stiffness related. Shocks only impact that type of balance when you're transferring weight around (into a corner, out of a corner, etc.) So if you don't go back up on tire size in the front, you will want to run less front roll stiffness (lighter spring or looser swaybar) or more in the rear (heavier spring or swaybar). An adjustable swaybar is really the easiest way to impact steady-state balance, assuming you're at all in the ballpark and have everything else pretty close.

This all assumes you have the alignment nailed and don't want to raise or lower either end of the car (as you'd need to get it cornerweighted again).

Good luck.

 

[ViperRay]

I agree with Irid.
Woodhouse sells an adjustable sway bar that I have set softer than stock up front to help with this.

 

[sun diego]

A bit of trailbraking will move some more grip forward.

 

[Brad Manhattan Beach]

I would check your caster settings. I have mine pushed to maximum and I have zero understeer.

I hope that it helps.

Brad

 

[Catwood]

Caster is at 5.8 and 5.9. I really don't want to corner weigh the car again. I don't have the scales. I'm going back to the track in a couple of weeks, perhaps I'll put the 315s back on for that weekend and see.

Thanks,
Carl

 

[luc]

How much - camber do you run?


Luc.00GTS

 

[Catwood]

-1.7/-1.8 front

-1.4 rear

 

[GTS Dean]

Not enough. I'd add a half-degree on each end.

When running narrow fronts, you need to compensate with rear steer. Let the fronts dance lightly on corner exit.