Got a call from a friend that said he is selling his Australian 9" Positive Traction rear end. This will bolt in my camaro without modification. I know this rear end is better than what I have now a weak GM 10, so im looking for some opinion before I buy this rear end any comments please. How much Horsepower can this one take? Is it worth $300.00 that he wants for it?

I'm no expert, but I know the 9 bolt's a lot stronger than the 10 bolt. Not sure of the rating though.

I also know rebuild parts are outrageous for them too.

If it's complete, and in good order it's not a bad deal IMO...

If its a 2.77 or a 3.08, its pretty much garbage as far as performance goes. The only part you can use is the case. Everything else has to be junked if you want gear ratios resembling anything decent. Check the condition of the gear oil as well. If its black and has lots of crap in it odds are the posi is just plain shot. If it has the delco calipers and good gear ratios (3.23+) then its a good deal. If its got the PBR brakes on it then its definatly worth it. No brakes or drums then see if you can talk him down a tad.

I recall that he said it had 3:4* gears and it complete with disc brakes. I'm going to go and look at it tomorrow and see what condition it's in. If everything is good Im will to buy a rebuild get to ensure that it will hold up to my engine. I'm almost finish with my SBC 409 and it should have between 475-500hp/tq. I really dont want to shell out almost $2000.00 for a Moser 9" or 12 bolt if I can get this rearend built a 1/4 of the price. This will not see a lot of track but I do want to change the gears to 3:73 to fit my overdrive tranny and have some good 1/4 mile times.
Where can I find a list of RPO codes for rear end to bring with me so I camn verify the numbers? I know I can just count the bolts but I like numbers for extra insurance of knowing exactly what I got.

If it has good gears in it and its mechanically sound then its a good deal. Keep in mind, though, that the carrier isnt much larger then the one in the ten bolt so its not super strong like a 9-inch will be. The things, IMHO, that give it the leg up on the 10-bolts is that it has pressed in axles rather then c-clips and the axles are 31 spline. Its stronger then a 10-bolt, probably somwhere inbetween a 10-bolt and a 12-bolt in strength. Some people have run some good times with then but I dont know how well itll hold up to a real hot combo. Maybe someone who has more experience can give you advice on how well itll hold up.

That's MY EXACT dilema too!! I am also expecting my 406 to be done by the end of Feb......and the builder is estimating "close to 500 HP" on the dyno - We'll see...

I plan on nursing my open 10 bolt till I can get a 12 bolt Moser. No choice, funds are tied up on my engine for now.

What about investing in the 9 bolt and paying the price to rebuild the rear end.
The package price for a new posi unit, gear set, install kit and delivery is $895 (lower 48) - New series 3 posi unit is $475 delivered (L48) - New gear set 3.2x-3.7x is $335 ($475 w/ install kit) delivered (L48) and 3.8x-4.1x is $355 ($495 w/ install kit) delivered (L48).
How would I know if I need a series 3 posi upgrade for the 3:73?

If it doesnt have 2.77's or 3.08's then you ahve the right carrier. Just give it a good inspection, put in gears of choice and rebuild the carrier with some new brake cones (assuming he still has them) and see how it holds up. Oh, dont forget new bearings all around but those will probably be included

That's just it. Even according to the prices you listed, I'd be spending closer to half the price of a 12 bolt to have a dependable 9 bolt in my car. Same as you, I'd like the assurance that it will hold up.

Let's say you end up spending the 300 for the rear, which most likely won't have 3.73:1 gearing you want. IF the posi unit is still good, well - lets see.

300 for the rear itself plus new gear set w/install kit for 475.....OK, it's not quite half the price of a Moser, but getting close. And that's assuming the existing posi unit and axles are in good shape. 775 bucks minumum....

Don't read this the wrong way DTL504, I may end up going the same route you are!! But considering a 12 bolt will hold up way better than any 9 bolt, it's a tough decision....at least for me.

That's why I'm also interested in this post.

What about dusting off the welder and cutting torch and getting a 95-up Ford Explorer 8.8? It has large disc brakes, 31 spline axles, 3.73 or 4.10 gear with Trac-Lok and it's strong enough to support 500hp 500tq. They're also very cheap. Oh yeah, and it's like 2 inches shorter track size so you can run slightly wider meats in the back

iroc22 - You may have a good idea there! It may be well worth "Exploring" into further (bad pun )

I don't weld myself, and I wouldn't choose a project like this to hone my skills - so I'd have to pay. But I'd have other questions, like the E-brake hookup, brake line hookup, what proporting valve etc...and running a Ford bolt pattern with adapters on the rear isn't a turn on either. Sounds like the best way to go though!! Hmmmm.....

IMO
If you can get a good 9bolt and install some good parts into the rear end it should hold up behind 500 hp/tq. Now if you spend 85% of your time on the strip then yes the Moser will be better for your situation. By beefing up the 9bolt with some good gears and changing the bolt to some good ARP bolts to hold the axle should be able to handle the 500 hp/tq. I would be nice if Miles aka www.9bolt.com was to chime in on this and see exactly what it take to get it to handle the hp/tq we are talking about. I will go look at the rear end tonight and give some feedback later. I know it is complete w/disc brake and he said he is selling it for what he paid for it. We will See.....:hail:

Just make sure it doesnt have 2.77's or 3.08's in it otherwise youll be spending alot of money on 31 spline axles and a new carrier in addition to what you already have to buy.

I've been putting 500hp/520lbft with 1.7x short times for 5+ years now behind my big block. Turbo Trans Am guys are running 1.6x shorts and low 11's all day on stock 9 bolts.

Miles

Sounds like a plan! I only want to take occasional trips down the track just to see what it does!!

If a 9 bolt will hold, I guess I'll end up going with one. It'll have to be next winter's project though......the wife is still a bit upset over the cost of this engine for now!! Time should heal...

They never understand.....

Well I went and check out this rear end last night and it was a 9bolt but had the 2:77 gears and a 2 series. So the search continue for a rear end 3 series or maybe I will convince the wife that I need a Moser 12 bolt. RIGHT......

You can get 3.73's and install kit from Randy's Ring and Pinion for around 320 bucks shipped.

I don't really see it worth swapping in a new only a 2nd series 9 bolt. You guys might check on ebay once and awhile there are a few 12 bolts and 9"'s on that from moser that people are selling out of their 3rd gens.

Where are you located? I have a 373 9 bolt that I built 2 summers ago. I am thinking about going with some different gears or a whole new rear. I have about 700 in the whole thing and it has about 7000 miles on it. I may be interested in selling just the gears and going back to the origional 327 gears or possibly the whole rear.
If you are interested in either let me know.
Kory

9 bolts are stronger than 10 bolts due to the 4 pinion gears in it vice the 2 the 10 bolt has.

I have a line on a 3.27 9 bolt complete with the big PBR rear brakes if you're interested. Drop me a line, I'm pretty close up in SC.

Ed