Bobby Smith

Anyone here have a link or info on running a 996GT3 in SCCA SS street tire class. I've been autocrossing in E/M for many years but the street tire classes are a new ball game so seeking info on quickest tire, tire pressures, alignment, sway bar settings etc. I'm currently running Rivals in 315/30-18 and 245/40-18. Just not sure it's the quick setup.
Any help/thoughts appreciated.

85Gold

I haven't run the rivals, I only have run the AD08 Yokohama, but I believe they have a soft sidewall so tire pressures I would shoot for 36 front 38 rear pressures as a starting point. -2.8 camber front with 0 toe in front. Rear -2.0 camber and .10 to .15 toe in each side in rear. Front bar full stiff and rear bar 1 off full stiff and adj the rear stiffness for rotation.

Peter

AudiOn19s

Hit up Aaron (loworbitsi) he should be a good resource to help you out. I believe he campaigns his car in both SS and SSR depending on the event.

Pretty certain he has 275/315 Rivals for his SS setup.

loworbitsi

Yes, I have run the car on a set of 275/315 Rivals. It's a mainly a SSR setup with 255/315 A6s, but I have the Rivals as my "rain tire" / drive around town setup. The 275s make the rear really tail happy, and you can't do full lock turns or it'll chomp off the upper brake ducts. I've found that the tires liked lower pressures in the high 29s. It seems that I personally like the tires a bit lower in PSI, but I'm working on just R&D with all sorts of pressures / settings.

From spending 99% of the autocross runs on the A6s, I sometimes feel that the car is "too fast" for the street tires to be really competitive in SS.

Bobby Smith

The Rivals have a very stiff sidewall. Some of the stiffest my tire mounting guy has seen LOL. I run 32lbs front/36 rear. I started out with Front bar 1 hole from full stiff and rear bar center hole. She pushed like a pig. Went to Front 1 off full soft and rear full firm. Now has excellent front grip but rear is loose so I'll leave front alone and go to middle hole in rear bar. I may have had the push in the front because I have not optimized the camber in the front. This is mainly a street car. The car really responds to sway bar adjustments.
My main question here is about tire choice. I'm thinking the Dunlop Dirrizas may have been a better choice??????

85Gold

Direzza doesn't have a big enough rear. The only other option is the AD08R which is only good this year. Get an aggressive alignment and reducing rear toe in is key to getting the rear to rotate. The stock setting is too much at .20 per side for AutoX. The ability of the Porsche to put power down on corner exit is it big advantage.

It is funny how different driving styles affect setup. When we ran SS 2005 thru 2007 with Ian winning in 07 our setup was unorthodox compared to Gary and the other GT3's He drove my car and it was way to loose for him, we also ran 245/35 front and 285/30 rear A6 for the gearing advantage of the shorter tire.

Peter