Turbo S 17" boxter twist wheels tire options
 

I have some 9" boxter twist wheels and the tires are 255/40s, a little too close to the fender up front and on the back the wheel and tire just looks too small. How should these be set up? I was thinking some 255/45s on the back and 245/40s up front does that sound about right?

The car is stock

First off, Boxster wheels are staggered. 7.5" up front , and 8.5" in the rear.

If you have 4 rear rims that are 9" wide, they are from a 911, and not a boxster

Ive run up to 235 on the fronts, and 255 on the rears. Im sure you can squeeze in a size up...