I have a 79 formula firebird and i want to swap my 2.7 drum break rearend for a disk rearend and even better one with 3.2-3.55. i want to be able to get one from a salvage yard. in doing research it was not clearly spelled out what models and yrs i could get a disc rear end. also does anyone know if there is one that will just bolt up where the original one did?

 

Third gens are 82-92. They use a torque arm suspension. Your 79 uses leaf springs. The diffs are also completely different. You might have better luck asking on a first/second gen forum.

I don't even know if there was a second gen rear disk brake option. If there was, they wouldn't be very good. You'd be better off installing an aftermarket system.

 

there are rear disc brakes for second gens, my old 81 Turbo trans am had stock rear disc for what its worth. I wish they would have kept the 8.5 inch 10bolt for our cars, just make it with the torque arm. Just think of how much money wed save if we could just beef up a stock 8.5inch 10bolt, instead of having to swap to the aftermarket rears...........