How Much HP Can a 8 3/4 Handle?

Yes!

The rear ends life is based on many factors. That is one of them. Strength of axles, how well it hooks and on what surface, size of components, strength of components, car weight and distribution of weight, power (Engine torque) trans gear ratio, rear gear ratio.

It is no secret this area falls under bigger is better. The 8-3/4 will only last so long under so much power. The DANA 60 is pretty much the last word in strength. There is also the aftermarket Ford 9.