the tire width & rim width are two diff things. most guys nowadays are stretching tires like crazy. ive seen 215's on a 9.5" rim. but to answer your question just look over what other guys have done on this site
btw, i have 225/45/17's on 17X8 +35 all around and only rub a lil on dips cuz the car is lowered 1-3/4' in the front.
http://www.rimtuck.com/thumbna...to=94&