now for the posi rear end

[FrankC]

Thanks to some of the guys here i ordered my flowmaster mufflers so now i need help with my rear i need to get a posi rear end dont know to much on that subject so again if you guys could give me some advice here i would appreciate it my camaro is an 81 with a V8 350 mild edelbrock cam, performer intake and 600 cfm carb and hooker headers with 3 inch straight pipe no cats and waiting on my flowmaster 40 series mufflers. so if any of yall can help i appreciate it thanks again. FrankC

[BBCAM]

You cant go wrong with a EATON posi unit they are reliable and plenty strong for a mild built engine , there are others out there that work well also but any 8.5" unit will work .. you should check your rear end gears and see what you have stock as you may want to change to a better gear 81s arent known for good gears ( usually in the 2.41- 3.08 range) Z28s even had poor gears that year , if you dont want to put a new posi unit in it and would rather just change out the entire rear end look for a rear out of a mid 70s 74-78 trans am with a stick lots more of them were equiped with posi and good gears and they are a direct fit I would still suggest pulling the cover and checking for gears and posi but it might be easier to put the entire rear in unless you know someone who can set up gears and stuff...

[FrankC]

Thats what i would like to do is change the entire rear out and find one thats posi and that would bolt right up if i can that would probably be easier and faster i think. any way thanks for the info i didnt know that 70's trans am would be a direct fit. FrankC

[btchncamaro]

any camaro firebird trans am parts are pretty much exhchangeable from 70-81. try looking in the local paper or trading times or something for a rear nearby. i see 10 bolts around here going for 250-500 usually depending on the goods.

[FrankC]

Yeah i seen one today but dude had sold it, so im still lookin i am goin to get the news paper tommorrow and check it out i heard there where a couple in there but i wanted to make sure they will bolt right up i dont really have to much time right know to fab any thing. Later FrankC

[btchncamaro]

make sure to take measurements of your old rear, drum to drum, and leaf spring perches, etc.

[BBCAM]

The only thing to watch out for is the early 70-71 rears were 8.2" ring gears after 71 they are 8.5" you will want an 8.5" the dimensions are the same weather it's out of a bird or camaro, width and spring perch wise 70-81 the only difference being some were offered with disc brakes in the late 70s which will fit but require a different brake set up and master cylinder...

[mike mitchell]

go with the 78-81 trans am rears. if you find a turbo car it will have rear disc. they should have a 3.42 posi. if you get one, make sure you get the master cylinder and porportioning valve too.