I want to get posi and I have my stock 3.4L rearend...I just want to get the posi unit rather then the entire rear end (I need the 3 series, don't I?)...What posi unit do I need to get?

 

Why not buy a complete rear axle assembly out of a V8? That will get you both the posi, and the rear disc brakes. Just try and find one from an M6 car, so that you get at least a 3.42 ratio.

If you just want to change the center section, go to SLP and look over their "takeoff" posi units.... taken out of Firehawk conversion cars with virtually no miles on them. Might still have some left. You definitely want a 3-series unit. That will allow you to move up to higher numerical ratios... 3.73, 4.11 with less issues.

 

I want just the posi unit becuase its cheaper and I don't have much money to spend...but I want to get posi for when I get my car back out in the spring.

 

What size posi unit do I need? I'm looking for one on ebay (I'm a cheapass...I only make $65 a week and I owe $40 a week) and I don't know how many splines it has to have, and what size gears do I need (as you can see, I don't know much abound rear ends...)?