Originally Posted by Trips

Lookin a little more into the rim size. If you go 21", rolling diameter stays pretty much the same, additionally you'd be able to run a 325 size tire, a little larger than the stock 315.

If you go up to 22", the widest tire you can do is 305/35. However, this size has a diameter which is 1.7" greater than stock. You'd have to go down to a 295/30 to get a similar diameter. Running the 305 size will cause a speedo discrepancy of 6% (when u r driving 60, u are actually going 63.6 mph). Also, you'd probably have to run a 10" wide rear instead of an 11".

Anyways, not sure if its worth the sacrifice in rear rubber width to run 22" rims.

_Tom

ps Did my calculations from this site: Tire size calculator
pretty cool!