Need advice on track setup. After first track day with just picked up 2007 GT3 I have some push that I would like to get rid off. Currently running MPSC tires, front sway at second position from full soft. rear sway is full stiff. Alignment is stock.

I would like to experience more throttle than I can now during mid corner. I would also like to keep streetability so running over 2 degrees negative camber at all times may be a bit much. I was thinking going from 235 to 245 up front if clearance allows, maybe just less than -2 camber and full soft on the front sway? Also switch to R888. The Pilots are not bad but do not feel sticky like R888's I had on another car.

Thoughts appreciated.

 

cant answer your questions but have a couple as well. what are the factory sway settings? whats a good setting for street?

does porsche have alternate alignment specs in the system for the GT3?

 

if you are going to track you should really get a proper alignment at a good independent or race shop as these cars come from Porsche with varying degrees of correct alignment...also, check your droplinks on your sways often as they come loose...here is a chart that will give you some ideas of things you can try to lessen the understeer...if you are already at full stiff in the rear you can go full soft in front and that might do it..you can also change tire pressures some but you may need a softer bar in front or a stiffer bar in the rear to get it in range...

 

You will have to try different setups.
My car is typically loose because the rear tires are not as good as the fronts and I come out of an understeering car, so I make it loose with my (wrong) driving style.

I run all soft rear and middle front and it was perfect for Road ATL 1:37 Laptime on hoosiers.

I did have the car setup pretty low and corner balanced, -2.3 front camer and -2.7 rear, or close to that.

 

thanks guys,

The chart was helpful. One comment - maybe I read the chart wrong - increasing front tire pressure should promote under steer, the chart I think read the opposite.

 

I also thought it was the oppsite when I read that

 

try it...you will find the chart is correct...here is similar data from Tire Rack:

btw...that chart assumes optimum tire pressures/temps...if your front tire pressures/temps are getting high for the compound adding pressure will not help understeer, which I think is where the misunderstanding comes from...this is a very fine adjustment and would only help very mild understeer in a well balanced car

 

Agree with most that has been said. One thing that you should do immediately is get rid of the stock Pilot Sport Cups. They under steer like crazy. In addition to a modified rubber compound, they have enormous rain grooves.

After you have nixed the cups, please try different sway bar settings. Most of us have settled on full soft in the rear and a middle or one from stiff setting in front.

As far as camber, -2.9 F / -2.4 R. You will not have problems on the street if you keep the front toe at close to zero.

 

^^Thanks for the info about the camber and toe, I was going to run around -2 next time I get aligned or when I put my coilovers in time and I was worried that I would run through my tires with that much negative camber on the street. Rep for you!

 

Before trying to diagnose bar settings, you really need a better track alignment, or at least something more track oriented than stock. If you aren't going to get a new alignment before your next event, just run the front sway on full soft.

FWIW, I run 315/245 on my 6GT3, sways at full soft (F) and full stiff (R), with a modified Kussumaul alignment. Car it dialed in and tire wear is even across the tread, and about 1:2 F:R.

-td

 

You got PM..

Mike