Im running 275/50/15 DR on my lx 8"weld 5.5 bs had to do some inner wheel well hammering and no quad shocks other then that they fit fine so Im sure those will fit no problem
6.5" would prob. be best. I recently got some 15x10 draglites w/ 6.5" backspacing w/ 275/60/R15's, but plan to get some 275/50's instead because the 60's are way too tall.
Jeff is right. 5.5" is ideal for that size tire on a 15x8 wheel. I used to run that size tire with a 4.5" backspacing and I had to roll the fender lip. So 5.5" is about perfect.
I have those size tires on Weld Draglites. 15x8 with 5.5" backspacing. They are pretty close to the exhaust, but they won't fit with the quadshocks. What I did is just take them off and flip them. They are VERY close but don't rub or anything.
I doubt they have a 6.5 bs for an 8" rim. 15x10's are supposed to fit, but i've heard it might be close. Gotta flip the quad shocks, beat the inner fender and maybe roll the fender lips a little bit.
You could probably get it on a 15x8 w/ 5.5" backspacing and many do, but the whole tire might not hit the ground evenly; the edges might pull up a little bit. Each tire manufacturer is different.
265/50/15 on 15x8 with 5.5" backspacing. Needed a 1/4" spacer, had to pull the quads (flipping didn't help), and reposition the exhaust. The only thing I'm not happy with is the tire height.......only 25.5". Otherwise no problems.
These issues with backspacing is why I went with 16 X 8.5" with 5.5 inch backspacing. It is perfect in and out. No mods needed.
Heres a little breakdown of how they should fit in the rear of a stock fox:
7 inch wide = 4.5" backspacing
8 inch wide = 5" backspacing
8.5 inch wide = 5.5" backspacing (I say the perfect size, no nods needed)
9 inch wide = 6" backspacing (very close but works, flipped or removed quad shocks, possibly moved tail pipes)
10 inch wide = 6.5" backspacing (with inner and outer fender work, removed quad shocks, moved tail pipes.)
Heser a couple of pictures of my car with 16 X 8.5 with 5.5 inch BS and 245-50-16's Nitto DR's. View attachment 517853