I just bought a 2004 RX-8 and the previous owner put on custom rims/tires. The fronts are 225/45ZR18 95W and the rears are 255/35ZR18 94Y. Looking at the manual, the fronts match the recommended tire sizes but the rears do not. What kind of impact is this going to have, if any? I've read a bit here about understeering with this configuration but what about the speedo being off, the LS differential not working as well, DSC, mileage, etc?

Also, should I be inflating these tires to the recommended 32psi or something different?

 

You're going to be putting more miles on the car than you're actually driving. You need to get a 255/40 for the rear.

Or better yet. 245/40 front and 275/35 rear.

Rishie

 

What about tire inflation?

 

Why would someone want different sizes front to rear i wonder.

 

Read the other threads in this forum; there's been plenty of debate about that already.

 

Hmm. have'nt seen any let me search.

 

Tire inflation is also up to you. I do anywhere from 32 to 36 psi cold.

Rishie