Rear leaf spring Question 74 Dart

A 15x7” with the proper backspace for the axle you have works great. The backspace IS different for 8 3/4’s vs 8.25’s and 7.25’s to max tire size though. Some have even managed to get 255/60/15’s on their hard tops with the spring in the stock location. That’s unusual, it’s much more typical for a 245/60/15 to be the max on a 15x7 with the stock spring locations. There are always exceptions, but a 245 is usually a pretty good bet if the backspace is correct.

@toolmanmike has 255’s on his hardtop Dart
70 Dart Swinger with 275/60/15 E/T drag