245/60/15 on 66 Valiant

I ran 15x7 on my 66 dart but had 4 1/4 back spacing. I had my rear leafs resprung on the 7 1/4. They would rub only if I had someone in the back seat or loaded trunk and turning corners. I have 225 60 on my 65 dart because I didn't want any rubbing ever. And I dont