It would depend on the tire's width. For a 15" rim you could 'probably' go with just about any standard steely positive offset and it would be fine. The worst case scenario is that the tires would hang outside of the fender area a little -- that would be your only possible rubbing point (on the outside edge of the fender). I have a set of 16" rims on my MSP with +40 offset and they are basically just as good as the stock +55 offset. No fitment issues whatsoever.