whats the best rear end for my 91 rs with a 700r4 and a 350 TPI and where can i get it

Can we assume you mean gear ratio?

JamesC

you could say that.
what happened was,i got in an accident with my 88 iroc and really wrecked the frame.
It still drives fine, but it sounds like theres a little grinding kinda noise coming from the back when driving it.
It kinda feels like its not riding as smooth as it did before the accident.Shop told me the 4 wheel alignment was not off and that the frame damage was in front of the front wheels.

im not sure if im going to need to replace the rear end,or what ever part of it that may be damaged

i plan on swaping these parts into my 91 rs

Aside from the fact the 88 rear may be damaged, here are some things to consider:

You'll be going from 28-spline axles in the 91 to 26 in the 88.
If the rear ends have different ratios, you'll need to swap drive and/or driven gears for the speedo to read correctly. (Those are a direct swap if both cars have 700R4's. If one's a T-5, the other a 700R4, then they won't swap and you'll have to purchase what you need.)
The e-brake may be an issue.
You'll need to swap the proportioning valve for best performance if the 88 has discs and the 91 drums, which I assume it does.

JamesC

well,the 91 has no motor or trans in it.the rear end is still in(think the correct word would be the housing) it but i dont plan on using it.i plan on swaping the entire line.motor,trans, rear end...ect.il have to swap the engine harness,gas tank(for the correct fuel pump) and probably a few more parts.
the 88 has drums in the rear.
im not going to worry about the speedo for a little while.