Z28 rear ends

[dr_mario_05]

I got a 1995 Z28 with a few mods on it and i know the 7.5" rear end is a weak point, are there any stronger 7.5" rear ends out there made by other companies that will fit in the stock housing or will i have to do a 12 bolt or 9" conversinn

[Mike@Diablo]

Originally Posted by dr_mario_05

I got a 1995 Z28 with a few mods on it and i know the 7.5" rear end is a weak point, are there any stronger 7.5" rear ends out there made by other companies that will fit in the stock housing or will i have to do a 12 bolt or 9" conversinn

The 7.5 is a weakling. Lots of people have gone pretty quick on them, but your playing with fire if you have over 400 rwhp.
Beefed up 7.5s can likely handle more power, but the ring gear is still too small to take all that load.
A4 cars tend to do better with the stock rear than 6 speeds, just because they tend to launch/shift a bit easier.
If you plan to abuse the car, look into a 12 bolt or 9 inch, both of which are readily available to bolt into an F-body, with mounts for the torque arm and all.
Strange recently released a Dana axle that they say is even stronger than the 9 inch...

[nailhead425]

Generally the side gears will fail or the case will flex and cause the depth to change and spit the pinion gear. You could look to aftermarket chrome moly axle shafts and a heavy duty diff. In addition a diff cover that has a gusset and bolts to preload the bearing caps would be worthy. Even with all the tricks the 7.5/7.625 axles are low on torque capacity.

A Ford 9" requries the greatest amount to torque to turn, due to the low pinion gear position relative to the ring gear, the 12bolt is likely the most efficient, and the DANA 60 might be the best of both worlds.

Don't forget your C-clip eliminators and new driveshaft for the HD u-joints.