Duster 275/60/15

Dusten said
I have 71 Duster with stock A body 8.75 rear end with small bolt pattern and springs in stock location. I am looking at getting 15x8 rallye wheels form wheel vintiques and putting 275/60r15 on them. The wheels only come in 4.625 back spacing though. They do custom back spacing at a price though $50 a rim. I have made the measurements and done the math it looks like 4.5 would be ideal back spacing. These are so close, just 1/8 inch more back spacing. The math says they will fit but will be close. Was wondering if anyone has real experience running the 275 tires with 4.625 back spacing?

If you were running big bolt pattern axles I’d say go for it, it’d be close but it would probably be fine. With SBP axles you’ll need a spacer for sure. That’s ok if you use a good quality spacer, but you’ll also likely need longer wheel studs too.

hoosierdaddy said
I'm running the 15 x 8 rallye wheels on my 72 Duster with a 255/60/15 and I don't think you'll make the 275 work . As far as running a spacer it will help but you'll need to install longer axle studs to use them . I'm not running spacer and I'm still going to replace my studs this winter because there is only about a 1/2" of stud sticking out with these wheels .The picture posted is my right rear and its real close but I have never rubbed . The left side is a non issue .

View attachment 1715387820

hoosierdaddy said
Your 275's are no closer than my 255's . now I need to know whats wrong with my car . BTW love the color , nice work

If that’s your clearance with 255’s you’ve either got too much backspace on those wheels or too narrow of a rear axle.

It’s important to know which rear axle you have and what bolt pattern you’ve got. A-body axles are not all the same width, 7.25 and 8.25 rear axles are narrower than A-body 8 3/4’s, even 8 3/4’s with small bolt pattern axles. And on that note, BBP axles also change (widen) the rear track width. The backspace needed with a BBP 7.25/8.25 is almost a 1/2” different than what you’d want with an 8 3/4 with BBP axles.

TF360 said
4.25 BS with a 255's- Don't go bigger unless your ready to modify.

Yeah that’s just not true. Depending on the axle even those specs might not necessarily be good advice. And there are quite a few Dusters, Demons and Dart Sports with 275’s and no issues.