alot of it will depend on positive or negative offset of the wheel. me and a couple of other mark owners run 315's in the rear. on my first set no mods using nittos. on the new wheel combo, im going to have to message the inner fender well alil. i run a 1/2 inch spacer also. as for front ive seen as wide as a 275 up front. i run 265's, but the type of wheel im using has them poking outside of my fenders. so some modding will be done to get the right look back.