A freind with a 69 camaro has this auburn posi unit out of his car. My 69 firebird has the original 8.2 10 bolt. Will this Auburn unit fit my firebird? This unit has "C" clips. Mine doesn't????? Would new axles solve this issue?
Who is willing to bring me the disappointing news with a brief explanation.
Your 8.2 is stronger than the Chevy rear, believe it or not. You can get an aftermarket carrier to build what ever ratio you want. Auburn & Eaton would be good choices to go with, axles would work from old rear, but if you go through the trouble of building a rear, may as well put better axles in.
I don't think it would be cost effective. I am considering going with one from drivetrain parts on e-bay. About 700$ with gears carier berrings and install kit. Our Pontiacs are supposed to be stronger than the Chevy also. I am just trying to decide if the eaton is a couple hundred better than the auburn? The Eaton is rebuildable, auburn is not.
As far as memory serves, the Auburn "Pro Unit" is the only aftermarket "posi" for the BOP 8.2. The Chevy units DO NOT fit.
The Auburn in Scott's '68 IS "rebuildable", as it's a clutch-type. And yes, it's been mid 10s with slicks and "lived" just fine. A Chevy 8.2 would break if you sneezed on it... No comparison in strength. We DID add Moser axles, though.
My 68 has the 10 bolt stock [non C clip] rear with stock axles and an Auburn 373 posi installed. It handles the 428's torque just fine and only cost a bit over $300. If I can find the receipt in my p. poor filing system I will post the auburn part number. Al.
That's good to hear. My engine builder seemed to think that I was going to blow up the 10 8.5" with the 428. Of course he thinks it should have 4.10 gears too.
You can also get an Eaton. I think Auburn offers 2 choices I guess one is rebuildable, and I know one is not. I just ordered the HD Auburn and a 336, can't wait to try them. I don't intend to spend a lot of time at the strip. I see no reason it will not hold up. E-bay about 700$ Gear diff and installation kit.
I have the Auburn Pro Posi and 3:55 gears, stock axles behind my 468(with street tires) No issues...and I abuse it as often as possible. Might be a different story with stickies...
I'm a hobbyist. Not a professional. Don't be hatin'!
The Chevy posi unit WILL fit the ponitac housing and the series offset is 3.36 and up for that unit. The axle spline on both units are 28 BUT the BOP 28 spline is 60 degree cut and the chevy is 45 degree spline cut making the bop axle slightly loose in the side gear unit.
BUT it will fit and can be used under lower torque loads (regular driving etc.) ANYway it is better to get the correct part always.
AUburn sell both pro and HP units for the 8.2 Pontiac 10 bolt. I would stay away from the PRO unit as it really is set-up for race duty and will wear the cones out much quicker on the street with all the turns that will be done. HP Auburn will do you better. They come in 2.93-3.23 or 3.36 -4.33 and beyond.
700.00 is about what we sell the posi rebuild kit and set of gear for too. So that is just about right on.
Just remember INSTALL is the biggest thing to make any drive line item to stay together under performance applications. Gear pattern and backlash are key and properly torque to specs.
3.36 3.55 3.73 3.90 are all available for aftermarket 4.10 and 4.56 4.88 were available too but becoming harder to find these days as no one is buying those ratios...we just do not need to race the 10 bolt 8.2 anymore with all the other larger rear choices. Jim J D Race.com
Picking up the Eaton myself everyone I have talked to says it's the better unit going with 3.55 gears. By the end of the next few months Jeg's will love me.
