Hello
I recently found that the rear end in my 69 camaro 10 bolt is not positraction. (Tires spin independently when up on a jack) I'd like to remedy this. I guess I have two ways to go- 1) get it built to be posi or limited slip via aftermarket parts + have someone do it for me (no experience in this department) or 2) find a replacement rear end.

It isn't important to fork over the big bucks for an original 69 rear end even if I could somehow locate one. I would consider a rear from any Chevy if it will bolt up without causing hassles and reworks.

I am interested in opinions on the more simple way to the goal, plus suggestions on donor makes/models/years that will bolt up without causing all kinds of grief.

thanks!

Try and find an 8.5" unit from a Nova or related vehicle, 71 to 74 I think, maybe up to 77. You can also get a posi unit from a Trans Am or Z-28 with same rear to put in it, the rear won't fit cause its wider but the Nova unit should bolt right in (I got one in my 68).

thanks bill... so you are saying that on old z-28's and AM's, the axel itself is too wide but all the stuff can swap?

that's a very real option too. far tougher and not as big $'s as I would have thought...

I have a 3 Series Eaton Posi I can sell you for your Original 8.2 Rear.
8.5 10 Bolt Nova Rears are a direct bolt in.
1970 and Up Camaro Rears will not fit.

Here is a Link to identify the different rears:

http://www.novaresource.org/axle.htm

How do/will you use the car (drag race, street only, road race, ...)??
What engine/trans combo are you running (small block/big block, manual/auto)??
Do you plan on changing the rear gear ratio also or do you just want to be able to do two-wheel burnouts??

Sorry for the 20 questions, but the above info will help guide you towards a better answer (in my opinion).

The stock 8.2" 10-bolt is not known for it's overall strength, but for street use, it should do fine. If you're planning mostly street and are happy with your current rear ratio, then I'd say to drop in an Eaton posi on your current rear.

If you're planning to change rear axle ratio as well, then I'd strongly consider looking for an 8.5" 10-bolt rear out of a 72+ Nova. This would be slightly more expensive than changing ratios/posi on your existing rear, but will result in a stronger rear end.

If you're really planning on drag racing the car hard, then just step up to a 12-bolt or 9". Better $ spent in the long haul.

Hey T-
Good questions. Here is the low-down: 383 stroker, 410 HP and 425 Torque. Running that through a TH350 with a 2500 stall converter. I think the chinck in the armour thus far is the tranny with that torque number but it's doable if I don't run it too hard. I have a big cooler for it and plan to watch temps closely.

Surely two wheel burn outs are a goal, that's a lot of fun. But I also would like this car to handle itself ok at a test and tune at the track from time to time. Nothing extreme, don't want it set up as a drag car, it needs to be streetable hence my choice on the stall speed.

So with all of those variables let me know how you'd go....

An 8.5 will hold up to occassional application of power. The actual weak point between the 8.2 and 8.5 is the thickness of the pinion. From 1972 through 1975, all Novas were equiped with the 8.5 rear. In 76 only 350 4 speed cars recieved them 77 through 79 they were installed in V8 cars with a manual or automatic. All 6 cylinder cars received the 7.5 inch rear.

PA I sent you a PM with some options. Let me know what you think.

The 8.5 is a fine inexpensive strength upgrade, but a nova rear will most likely have the same "didn't come with a posi" situation you are in now.

You didn't mention anything about gear ratio, again, a nova rear will most likely have the same 2.73 or 3.08 gear that you probably have now.

Hey Jim-
Good call out on potentially getting a stronger rear from a Nova but no positraction again.

I didn't mention my gear ratio target because I haven't yet formed an opinion. I would like some opinions. My car's specs are above. With this set up, how much acceleration could you enjoy with higher gears without negatively affecting street driveability? Maybe mid to upper 3.xx's? Stock 3.08's are reasonable but there is probably something more aggressive that doesn't come at a huge penalty.

The 3.23 and 3.42 are popular 8.5 gears. The 3.36 and 3.55 are popular for the 8.2. The 3.31 and 3.42 are popular for the 12 bolt.If you get on the highway much then the 3.23, 3.36 or 3.31 would be a better choice. If you stay in town or close to home then the 3.73 is available for all 3 rear ends.

I think my vote based on your info would probably be an 8.5" with 30 spline axles, Eaton Posi, and 3.42 gears or (like Freddie mentions) 3.73's if you can live with "about" 3200 RPM at 65mph.

I figure if you're going to change gear ratio and the diff carrier on the 8.2", then the only parts you'd be re-using are the housing, axles (maybe) and the brakes. If you wanted to, the axles and brakes would swap between an 8.5" and an 8.2", so at that point, the difference between an 8.5" build and an 8.2" build is the cost of a "good" 8.5" housing (somewhere in the $150-$200 range?). Cost of the posi, gears, install, etc is going to be "something like" $700 or $800 anyway, so I figure the added cost of the 8.5" is worth it. (Note that most 8.5" rears are set up for multi-leaf and most 8.2" rears are set up for mono-leaf, so there may be some more cost in getting the 8.5" to play with mono-leaf springs if you still have them)

I have multi leaf springs? I just assumed they were original, they look like they are.

Maybe I should re-look the diff... hard to measure a difference between 8.2 and 8.5 on an oddly shaped object. Perhaps there is an obvious difference in the cover?

Maybe I should re-look the diff... hard to measure a difference between 8.2 and 8.5 on an oddly shaped object. Perhaps there is an obvious difference in the cover?

From the Nova Resource link that Tory (Camaros-n-Chevelles) posted ;)
http://www.novaresource.org/images/rears.jpg

There are other differences in the pinion spline count, pinion yoke nut size, and ring gear bolt size, (I don't recall the details) but the "two square lugs" is a quick and easy check for the 8.5"

For mono- vs. multi-leaf springs, the things to check are the lower shock mounting plate and the spring perches on the axle. The mono-leaf shock plates are thinner metal and use a double-shear mount (metal, shock, metal). The multi-leaf plates are a lot thicker and use a single-shear mount on a stud. On the rear, the multi-leaf spring perches are a LOT deeper than the mono jobs. Search around here for some pics...

Thanks. Almost certain I've seen those lugs on the bottom.

Save up your nickels and dimes to buy a Moser F-body bolt-in with either a Eaton Posi or Detroit TrueTrac with 33 spline axles. Then you won't have to worry about whatever you decide to put in front of it. It's only money....


http://farm3.static.flickr.com/2549/3802430254_ca3a4d1acd_o.jpg


http://farm3.static.flickr.com/2624/3897031787_7db66022cd_o.jpg

That IS rather glorious. Nice pic!

ahh, but one can do glorious rear end car porn on a more subtle budget too.

Here's my nova 8.5", stock 3.08 gear works well with my TKO 5 speed. eaton posi, moser 30 spline axle, and 1/2" studs from feddie, and wilwood 12.2" disks to cap if off.

Looking good Jim. I thought I had found a bunch of those 8.5 rear ends, but nothing has come through yet.

FYI -- looks like Jim Mitschke over at JD Race has an 8.5" up in classifieds-land. He's over in Richfield OH...
http://www.camaros.net/classifieds/showproduct.php?product=37570&cat=all

An 8.5 will hold up to occassional application of power. The actual weak point between the 8.2 and 8.5 is the thickness of the pinion. From 1972 through 1975, all Novas were equiped with the 8.5 rear. In 76 only 350 4 speed cars recieved them 77 through 79 they were installed in V8 cars with a manual or automatic. All 6 cylinder cars received the 7.5 inch rear.

The 8.5 does NOT have a weak pinion-it's plenty big/stout.The 8.5 will tollerate alot of power regularly - thats why they quit making 12 bolts and 8.2's. The 8.5 would be more than up to it for this application! It will probably require the driveshaft to be shortened due to the length of the 8.5's larger pinion

Brian, I want to know why you needed a jack to find out you didn't have a posi. From your engine combo I would think black rubber on the road would have told you. Get on it man!