What he said. Or were you referring to "stock" vs say, a Bronco converted to a buggy, or at least tubbed to some extent?
And the rubbing of the radius arms has nothing (or very little?) to do with the amount of lift present. Suspension OR body. it's all about the width, height, wheel width and offset that you're describing.
So with 12.50's and assuming 3.5" backspace (max of 3 5/8" for a '77 anyway) on 10" wide wheels, I'd say no more than a 31" tall tire before rubbing!
;D
If you adjust your steering stops however, you can go as wide as you want. You just lose a lot of your turning radius.
And no, while I might not be perfectly accurate, or exaggerating just a little, I'm not joking either. Even 31x10.50 tires can rub a radius arm if the wheel width and offset is wrong. My 32x11.50's on 8" wide wheels rubbed like a big dog.
With a 12.50" wide tire, anything over a 32 on a 10" wheel is likely to rub at full turn. Going to a narrower wheel will just make that worse. Going to a wheel with more backspacing is going to make it worse even quicker.
With that much lift I assume you're hoping to fit a large tire? You can easily fit 37's with that setup, but will rub the radius arms long before that. So put the tire you want and then adjust the stops. And when that doesn't work, spend for some aftermarket "bent" radius arms. This bend in the area where the tire would hit allows for more clearance.
The right arms are likely to be the most effective way of getting larger tires without rubbing. And being able to keep the EB turning radius.
Good luck.
Let us know what you were hoping for anyway. And I'm sure others will point out if I overstepped any of the pertinent info. But if I did, I don't think it'll be by much.
Paul
