There is a lot of variables when maximizing rear tire on a 70 Dart. I don't even think they're all the same and could vary a quarter of an inch from one to another. I know that my body is not perfectly centered on my tires it has about a half a centimeter to one side bias. But a 7 in rear rim with the right back spacing will give you the maximum tire spacing. I have run both seven and eight inch rims on the back and 8s will definitely spread the tire just enough to make a difference and rub sometimes with certain combinations where 7-in rim won't. It's also very important on the height of the tire taller profile will need you to set the car up higher on maximum tire width. I run a 275 50 15 on 8 in rims on mine with everything pretty maxed out. It takes a 3-inch leaf spring over Arch to accommodate. It's more of a street strip look and would probably rub with anything more than a child in the backseat.
















