Originally Posted by NISMOFO

12" should fit fine. I wanted to go 12 but don't really want the CF5 model. Thought about 18" but tire diameters are too small, but offsets offered are better.

325/30 was the size I would probably run, although Porsche has put a 305/30 on 12" wheels for the GT3 and GT3 RS in the past....I wouldn't try it with a hankook though.