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MSC81
04-18-2011, 09:42 PM
So just got a 8.5" from a Grand National to throw into my 81 El Camino. What I'm looking for is some insight into rebuilding it, particularly from those that have experience with it.

The rear is from an 85, has 3.08 gears, and no posi unit paid $130 for it.

My plan is to strip it, blast it clean, and put new everything in it, bearing, 3.42 gears, moser axles, posi, the whole 9...

Who has done this before? Have any suggestions on companies you like or dislike? Where to get stuff from? 28 or 30 spline axles? Paint it with engine enamel or por-15?

It's going in a behind a healthy 355 (375ish hp/400ish ft/lbs) that is street driven 3-4 times a month and will hopefully see some auto cross time when all is said and done.

I'm leaving this open ended for all kinds of responses so let 'em rip. Pictures are greatly appreciated.

Thanks.

Skip Fix
04-19-2011, 07:03 AM
If you don't already have a posi might as well step up to a 30 spline esp if you are going to use new axles. If going to do alot of drag strip action maybe welding the tubes to the center section-by someone who can do it correctly-jig and correct rod/wire.

Josh
05-06-2011, 09:49 AM
I would second that. If getting new axles is in the plan then make it all 30 spline. If $ is an issue, the stock 28's would live at your power level as long as you were not on sticky tires and bang-shifting at 7000rpm regularly. Moser, Strange, Eaton, all good companies. Welding the tubes is good if stepping up to power levels500HP +

chicane67
05-09-2011, 08:20 PM
I'll third. Especially, the idea of straightening the housing when done with any modifications concerning the tubes, etc.

But I'd nix the Moser ideas. Just my opinion.

jtm311
05-11-2011, 10:25 AM
I did that to mine. I also went with 30s and posi 373 grears also welded the housing. All seems good so far ;)
I never rebuilt one before this.
Here is the link with photos.
http://melexisfitness.com/Camaro_Pro_Touring/Album8.htm

John

sam 74
05-12-2011, 05:46 PM
i had a 8.5 behind a 450 hp 455/th350 combo, i did all the usualy upgrades, posi, gears, welded tubes and i added a support cover. i ended up twisting the axle splines because i used 28 spline axles, the only thing i didn't replace when i rebuilt it. definately step up to 30 spline axles and add the support cover on top of what the previous posts suggested.