Quote: rear fenderwell clearance: these are perfectly squared up with equal clearance on inside and out. rims have 4-1/4" bs.
Thanks for that Gary (and for all the pics). So the trade off would be whether to run with the 15x7 @ 4" BS or the 15x8 with the 4.5" BS. Either way, a 255 tire should fit (at least, it looks like it will).
If everyone is measuring backspace the same - the bigger 255 tire on a 8" wheel would be 3/4"+ closer to the wheel lip.
I don't think there's room for that.
Got me thinking now.... The section width on the tire in the photo (Dunlop GT Qualifier, 245/60/15) is reported to be 9.6" on a 7" rim. The Sportsman 255/60/15 is reported to be 10.25" on a 7.5" rim. Accounting for the difference in the backspacing, the Sportsman on a 7.5 rim would, indeed, sit ~0.6" closer to the lip. How much would an 8" rim change the section width?
I don't think there's room for that. 