I think the only way to know for sure is to measure up your car. There are too many variables for anyone to say with any certainty. Has the car been lowered or raised? Is it the stock rear end? Have the rear quarters been repaired or replaced? What age are the bushings in on the rear control arms and housing? Has the inner lip been rolled?
A lot could have been done at some point in the past on a 45 year old car...
As a best guess, I'd say they should work fine (assuming that's a 4.5" BS on an 8 inch rim?). It might be close so you might need to roll the baseball bat around to radius the inner lip, and you might get some rubbing in hard cornering if your bushings are getting tired. 275 60R15's are pretty common on these cars and they generally fit fine with an 8 inch wheel, 4.5" BS.
The 285 70's are almost 3 inches taller than the 275 60's as well (30.75 inches versus 28 inches). I've never run anything that tall on an A-body so I can't say for sure you wouldn't get some rubbing up top - especially on uneven ground with one wheel up and the other down...
Why so tall? Do you have short gears and you're trying to cut some RPM's on the highway?
Mike has chosen a 255/70 Cobra for now but he did find a photo of a 70 Chevelle with the 285s and we both think they look amazing on it . He has already decided to go with the 275/60 for MT/ET for playtime. Its all about the look as far as the 285s are concerned. Here is a photo of the car.
Absolutely, Mike likes the look but for now he has made his choices for rims and tires. He will definitely be trying these for fit in the future though. We both think they look badass!
Here is his choice for the rear.255/70/15 They look huge. Can't work on the car till Boxing Day so we'll post a picture of the car when we get them installed.
-- Edited by Willythickfoot on Wednesday 24th of December 2014 09:57:54 PM