gregg911

I want to get a dedicated set of wheels and tires for Auto X. The wheels would be removed and replaced with street tires after each event. I've got an 80 911SC and according to Zone 8 regs I can go DOT tread wear of 101-200 for +1 point or DOT tread wear of 50-100 for 2 points, I can afford the 2 points if needed and stay in class. Question is I am new at this and should I go 15" or 16", what tread rating, should I go higher tread rating and save the points for some other modification and finally what would you suggest in general?

I am fairly new at this so hopefully I haven't asked a stupid question.

Thanks for your help.

earlyapex

I recommend 15x7 (f) and 15x8 (r) wheels using 225/50 tires. Go with Kumho Ecsta V710, Hoosier A3SO5 or event Avon Tech R (225/45). The fast cars in GGR, Zone 7 are running these combinations. The DOT-R tires are worth the extra point.

RJay

I'd echo the r-compound recommendation. Worth more than virtually anything else you could do. I run 225/50 245/45 16s on 7s and 8s with Hoosiers which should work on an SC. Unfortunately if memory serves the 710s aren't available in those sizes. I beleive they have a 265/45 but I have no idea if that would work. Have to see how good the new hoosiers are. One thing to consider is that there are always sets of 16" early offset BBS wheels or thier ilk on EBay. I got one sets of three piece BBS wheels for around $300 and another set of HREs with BBS centers for $375. Bascially you can buy three sets of wheels for the piece of a single set of Fuchs 16x7 & 8 for. Admittedly a little heavier, but cheap and strong.

Jim Michaels

Several of the R-compounds recommended above have UTOGs less than 50, however, including the Kumho V710, Hoozier, and Avon. R-compound tires with UTOGs of 50 or more include the Kumho Victoracer V700, Kumho Ecsta V700 (but need to shave for any dry application), Yoko A032R, Yoko A048, and Michelin Cup. The Michelin Cup and the Toyo RA-1 are not very good for autocross, but are good on track after heated up. Of the R-compounds that fit the UTOG criterion, I recommend the Kumho Victoracers. They are the price leader, they work fairly well cold at autocross, they give good wear, and you can drive on them to and from events. The Kumho V710 grips better, but it has a UTOG of only 30, is soft and wears quickly, and one should not drive on them to/from events, as they are like slicks except for two grooves.

loosecannon

I also have a 1980 911SC and have autocrossed for 12 years. Over this winter I purchased 7 and 8 inch wide wheels and Kumho V710 225-50-16 tires at all 4 corners. They look great on the car but I haven't driven it yet and can't tell you how well it works. I purchased the tires from a 911SC owner on the east coast and he says they work great, and are reasonably priced. If you want staggered sizes, you have to run Hoosiers or Kumho Victoracers.

KenJ

I agree with earlyapex. 15x7s&8s w/225/50s all around. The slightly smaller diameters will give you a little lower gearing advantage too. Can you get away with lowering the car at all?... maybe an inch?

kj