1974 Duster wheels & tire size
... So, I need to get all new wheels. I want to go 15s, what back spacing wil fit best?
Stock back spacing on the poverty and rally wheels was 4¼".
And, what tire size will be best? I'm not going to be a speed demon, but, would like it to look and ride nice. It's my first car, I'm 16. It's a sort of project car, and eventually hope to be my daily driver. Thanks for any advice.
Depends.... Part of the answer is engineering, the other part is aesthetics. First, there are maximum and minimum rim widths that a given tire will fit. Second, given a rim width, there are a variety of offsets that will fit under the fender.
Here's where aesthetics come in. Most like the "full wheel well" look. Rubbing the tire on the inner fender is not liked. This is where the juggling of wheel diameters, tire sizes, and wheel offsets come to a head.
My experience: I have a 72 Demon that I converted to LBP and disk brakes. I scrounged a set of 15 x 7 cop car wheels (4¼ BS) that I mounted a set of 255/60-15 T/As on. The rears barely cleared the stock springs and the fender opening. The fronts did not clear the front fender opening. After calling Stockton Wheel and discussing my options, I tried a 235/60-15 and set the front fenders a little "wider". On occasion I have scuffed the tire on the inner fender, but the situation is not objectionable. When it comes time to replace these tires, I expect I'll go to a 225/60-15.
FWIW: I put Magnum 500s on a 73 Dart Mo-dor. After putting an AutoXCuda "street" front end setting, a factory front anti-roll bar, new rubber bushings, and a set of 205/60-15s, that car was a hoot to drive. It was a "momentum" car, no acceleration to speak of but it would claw its way through a corner well enough to hang with anything else with 4-doors.
Consider that the car originally came with 6.95-14 (aspect ratio was 82, FWIW). Anything you do will be an improvement.