New to the game here at only 21 i have a 79 camaro with a 12 bolt posi rear and coil over shocks came on it. I have herd that air shock will bust out the mounts because they are weak how ture is this running a 275/50R15 and they rub a lil on the inner fenderwells

 

I have an 80and am running 275/50R15 and they dont rub on mine!

 

Unless your car has had some major mods done to it the coil overs bolt inin exactly the same place as an air shock would. Most times when changing to coil overs the upper mount gets a little reinforcement to help carry the load. It is possible to bolt them in without doing this but not recommended. Also, normal air shocks are not designed to carry the entire load, they are made to supplement the leaf or coil springs.

Tire clearance depends on more than the tire size. Wheel backspace is what gets the tire centered in the wheelhouse. Take two cars with the exact same tires but different wheels, one may rub but not the other.

 

I'm thinking that maybe the OP is referring to shocks with springs (supplement), not true coil-overs?