Just bought some 18" 9.5" fronts and 18" 10.5" rear wheels. Looking for Autocross tires. The closest thing for the Bridgestone RE71R that I can find that I think will work and not set off the VDC is 255/35/R18 front, 275/35/R18. What I really want are 255/40/R18 and 285/40/R18. This car will be running in the Super Touring Ultimate (STU) class and thus can have tires up to 295 I believe. It is supercharged and heavily modified. So what is the best tire out there or what are others running in the 18" wheel set I am describing. Hours of looking already...LOL

 

I hear good things about the Nankang AR-1 they are 100tw though.

 

I believe STU calls for UTOQ of 140, but I'm just a road racer. I tried the Nankangs last year and while it's rated at 100, they're more like a 150.

 

Did some digging through the rule book and for STU it looks like 200tw is still the lowest you can go. You can run wider Wheels and Tires though. I am going to balance this all out for street and occasional autocross use with some 255/40r18 and 275/40r18. I know the 35 height tires would do better, may still get that, but kinda want to fill out the wheel well a little since the car is OEM height. Thinking that one over. With the 35 height I can get some Bridgestone RE-71r's. With the 40 height I can get some Goodyear Eagle F1 Super Cars tires.

 

Another to possibly look at would be Yokohama Advan, they have several tires in the 200-300 range.

 

Ditch the front wheels, get another pair of 10.5’s and run 285 or 295 all around.

 

I have to agree with terrasmak here. Square setup is the best setup on a Z. STU is going to limit you to a 285 tire I believe, but you should have a 285 tire on all four corners. Do a 285/35r18 if you want a slightly taller than stock tire. I have run a square setup for 8 years now and have never had any issues with VDC.

 

Well, I just cancelled my wheel order because Z1 cannot get them. Out of stock. So I can restart on this. Apparently, wheels are in very short supply right now.

 

What offset are you running on the 10.5's? Looking to get a square setup but not sure what offers work best. I'm also running a StopTech BBK fwiw.

 

My one set was +15 and the other set was +20