OK I have a 91 Firebird with some engine things done to it. I found a 12 bolt rear end out of a el camino with 3:73 gears and posi. I know the f bodies have the traction bar that runs along the drivehaft and it needs to connect to the new rear end. Is there a bracket i can buy or should i not even bother trying to fit this in and try to find a 10 bolt out of another car with posi and 3:73's?

 

dont bother with it....

 

If there was a bracket you could buy, if it really was just that simple, then most of us would have done what you are talking about a long time ago... but its not quite that simple. Problem is, theres nowhere to mount the bracket to thats stong enough to handle the stress, and welding isn't a realistic route either because the housing is cast iron - very hard to weld, and still iffy even when done right.

Plus, that rear end is probably either too wide or too short, end to end, so it wouldn't physically fit properly anyway.

 

There's nothing you can do to easily use the G-body 12 bolt in a third gen.

The width is different and there's no way to attach the torque arm. All the other mounts from the third gen diff such as LCA, shock and panhard can easily be cut off the 10 bolt and welded onto the 12 bolt but the center housing of the 12 bolt is cast so you can't weld anything onto it strong enough to hold the torque of the torque arm.

With lots of skill and fabrication work anything can be done but by the time it's completed, it'll probably be cheaper to buy a new aftermarket bolt in 12 bolt.

 

Ok, that what i thought but i figured i would ask. Thanks for the info, i'm going to skip that idea and just change out the gears thanks again