What size tires should I get for these rims?

Rims are sizes:
Front 17x7.5 offset 48
Rear 17x8 offset 45

These wheels came with tires that are 225/45/17 on Front, 245/40/17 in the rear.
I thought that setup give a lot of oversteer. Could I user 255 on the rear or should I reduce the size of the fronts?

 

With those offsets id go 215 in the front. 245 is prob already going to rub in the back with a 45 offset.

 

I don't think 245 will rub. This thread says they are okay
http://forums.s2ki.com/forums/index.php?showtopic=198597

Anyways couldn't I get spacers and run 255?

 

spacers are the wrong idea. You want the wheel to be going more inward not outward. +45 offset rear is going to be really close to the fender. Im pretty sure you will need to roll the rear lips.

 

Okay, thanks for your help