I have a 96 TA with 11" zr1's in back. I had the 9's before and they were 275/40/17 but I cant find 315/40/17 Nittos or anything for that matter. Does anyone know what size i should use or somewhere to find a 40 sidewall. Thanks.

 

Assuming you want to keep the same diameter tires, you should be looking for a 315/35-17 tire. You'll find plenty of those.

Dave

 

ok ill try that thanks.

 

The "40" in the tire size is not a "sidewall size".... its the ratio of the sidewall height to the section width of the tire. When the section width gets wider (275 -> 315mm) you have to reduce the sidewall "ratio" to 35%, rather than 40%, to get the same sidewall height. That's why they make a 315/35... so its the same outside diameter as the 275/40, as noted in the post above.