I'm running a 12in offset 55 with 15mm spacer. It wore a little in the liner about a 2in diameter hole but when I hit a hard dip the fenders rub the tire a bit.

 

I run a 12" ET40 wheel with -2.4º camber running a 315/35/18. There is very very little clearance (maybe 1/8") between the tire and the fender and that is with GT2 rolled fenders. There is about 1/4" clearance between the tire and the GT2 fender liner which is tucked right up agains the IC hose. I do not rub anywhere even under compression of which there is not necessarily much with 1500lb springs. With that said, it is absolutely critical that you don't rub the fender at the track especially with fragile tires like Hoosiers when they are heavily loaded. Cutting into the tire could lead to catastrophic failure. Most guys won't run a 30 series Hoosier on tracks that have high speed oval section because the tire won't handle the load on our rear heavy cars. It's fragile. The only way you'll be able to make an A6 335 work cleanly on a 12.5" wheel is if you crank in camber beyond -3º and even then it'll be super tight.

 

Sounds like its not worth the risk but that's just my opinion.

 

This is the best one I have on my phone. You can see that the current tire tread is actually a bit smaller than the wheel. I have an inch to the outside. So assuming 1/2 inch out and 1/2 inch in I should be good. Only problem could be the lower inside end by boost hoses. I'll try and get a pic of that later.

 

its 1/2 inch this way and half inch that way plus the spacer . Any chance you can borrow someones 335 and mount it and see what happens?

 

I'll only add the spacer if needed. I'm think if the boost hoses are an issue to use the spacer to push tire out and shim to add negative camber and gain space back up top. It's doable. Just have to find the right combo. Going to buy a cheap used tire to try fitment.

 

Going 235/40ZR18 and 315/30ZR18 Toyo R888's are they okay for DE and spirited canyon on RWD TTS, BBS wheels

 

Is that the R888? What is the tread width?

The hoosier slicks are fragile. The dot tires are super tough. Unless run on cups for some reason.

 

r888 or nt01 awesome tire.

 

I didn't think NT01 came in 315.

 

Yes, and I think they are better than the R888. Good street/DE tire but won't do anything for you and the lap times you're looking for of course. I bet my friend JR has a crap 335/30/18 Hoosier I could send you for a test fit.

 

I've run the NT01 before. Great tire.

 

The 315/35/18 I run is a Kumho V710. Great DOT semi slick. One warm up lap us all I need on those for best times. I won't run 888s, total **** after a few heat cycles. NT01s are the king for long lasting good to the cords tires. Obviously a couple of seconds slower than the A6s or V710s on a 2 min lap but value can't be beat.

 

+1. Once the R888's get greasy they are done for that session.

Grip level changes (not for the better) after a few heat cycles.

The NT01's are a great tire. You can drive on them to and from the track.

 

I have run the v710 as well. Great tire. New a6 were about 2 seconds faster than well used v710 on my car. New I think they are within a second of each other.

Hoosier just has a sweet contingency. I've won about 20k in tires since late 2011 mostly Hoosiers.