posi question?

[cooler26]

What rear came in the monte SS 7.5 or 8.5? And how strong are they? Can they handle 400 hp?

 

[85 Cutlass Brougham]

7.625 . Only the 1984-1987 turbo Regals and 442 Cutlasses had the 8.5. The 7.625 will handle 400hp depending on how you use it. If you plan on slicks, plan on a new rearend. It is unable to take excessive shock loading, which is what you get with sticky tires resisting the force of the engine's power trying to overcome the weight of the car. On street tires, it will last as long as you don't abuse it. 4th gen F bodies with the LS1 and 320 wheel hp ( around 350-400 hp gross at the crank) got the almost identical 7.625 axle ( 7.5 with 1/8in more ring gear dia.) from GM because street tires are not expected to hook up well enough to kill it. The weight of the 4th gen F bodies is similar to the G body with a SBC, so the load is also similar.

 

[Furtrader]

7.625 . Only the 1984-1987 turbo Regals and 442 Cutlasses had the 8.5.

The '84 Hurst/Olds also had the 8.5 rear end.
Oddly,the '83 H/O only had the 7.5.

 

[87MonteSS]

It also depends on the transmission. If it's an auto it isn't too bad but a manual will kill it quickly if you're planning on hard launches.