2.73 or 2.93 There are no repros rear gears for the Buick 1971-1976 9 3/8" rear and used ones in a posi carrier are chicken lips. You might find some in a 3.23 or 3.42 ratio used. Whether they will be noisy if inserted after a wear pattern has set up is another consideration.
Whats a "repros?" and is it the higher the gear ratio the better? Do you know where I can get a posi kit for my buick?
There are no such kits as no reproductions ( repros) are made. You would have to locate a used unit and they are hard to come by. I would probably not change the rear gear. Electras are so heavy they will never be a rocket ship. But for some modest money you could have the distributor ignition advance recurved or install an X pipe etc to improve performance.
I know i did some mtr work to it like cam,intake, carb. I'm putting 26" rims on there i just want to tracks when i burn out and i dont want to to get it welded to lock the rear end because im going to be driving it on the street.
Be careful as 72 was a low compression engine. Combining a low compression engine with a big cam will usually sound bad but actually slow the car down. So hopefully you brought the compression up during the modification.
Depends on how big the cam is... Good luck finding a posi carrier. It takes some people years to find them.
It doesnt have the original mtr, I bought it with a oldsmobile 350. 69-72 cutlass mtr. They tell me its called a 350 rocket.
Best bet is to find a rusted out electra in the "north country" as this is where these cars came with posi. I found one for my riv in an electra that was in NY. As I understand, all canadian models came with one.