I ran a 275/50/15 on my 70 Buick GS with 15x8 rims. I have seen people try to use 295/50/15 on the 15x8's but the tires look bulgy in the sidewall. I have 15x10 steel widened rims with 5 inch backspace and the 295/50/15's that I have now put on my 73 GS and I never had a rubbing issue ever with them on either car.