I don't know **** about rearends. Can somebody explain to me what the following parts are( I think I know what they are):

carrier
differential
limited slip
posi(is it the same as limited slip)

Can someone suggest whether i should get a whole mail order rear or buy go fast parts for my stock 83 rear? I want to go to 3:73's and if mine don't have it a posi unit. What is a powertrax unit is it posi?

Sorry for all the Q's bu thanks for any help.

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LONG LIVE THE MUSCLE CAR!!!!! MAY ITS REIGN NEVER END

1983Z28 350w/ edelbrock performer RPM power package with 64cc aluminum heads, dynomax shorty headers, 700R-4 with shift kit, 750cfm carb, edelbrock 3" exhaust system, ASCD SS hood, 16" IROC rims.

future mods:
completely done over suspension, black paint with flames, Hurst shifter, dakota digital gauge package, procharger supercharger.

 

Carrier is is the center section of the rear end "differntal", To tell if you have posi limited slip, you could pull the cover or look for rpo codes in the console.. Limited slip and posi are essnetially the same thing. different manufactures used different names for the rear, example mustnags have traction lock rearends.. Kevin