Rear End Question

[SBC Maro]

Hi there! In the Engine Talk section I have been asking quite a few questions in the last month or so trying to get my 355 all built. Well, Lo and behold, I did! As I await my last shipment from Summit (I swear to God they better send me a christmas card, I'm making them rich), I have began to wonder about the next step of this project, the driveline.

I currently have the stock 10-bolt 8.2" OPEN ( ) 2.73 rear end in this car, and I would really like to install 3.43 or 3.73s in it to wake it up. My question is this:
What exactly do I have to install to convert to a posi rear end?

I really don't know much about this area, and don't know what exactly I need. A carrier? Can I install it in my rear end? Can I use my old axles? Thanks alot, this is one area I can't wait to learn more about.

-Rob
(My 70 Nova wishes you all a Merry Christmas, you've helped her through quite troubled times this year )

[lt1s10]

you need a dif. carrier for the pos. traction, but you can use the some axles.

[TyphoonZR]

Rear End Question

I thought the topic sounded interesting.

As for the axles, you could use some axles as lt1s10 put it, but you could also use your same old axles.

[pro70z28]

If it were mine I would probably find a 12 bolt posi and start with that rather than putting money in the 10 bolt. Not nessesarily right or wrong, but it's the way I would go.

[mooneye777]

they sell an auburn carrier that is about the best one you can get, if you plan on running it hard at the strip with over 450 ponies regularly you should upgrade the axles also. if not the old ones will work fine. i had around 430 hp in my camaro 10 bolt with stock axles and pulled holeshots for several years at the strip and never had a problem. but they are good insurance if you have extra money lying around. and its a proven fact a well built 10 bolt can handle 500 hp in a race car all day. ive got an article on it and will post it if i can find it.

[Dave Severson]

I'm along the same lines as Pro Z, except I put a 9" Ford in everything... Are you sure that the 8.2 is up to the task of big horesepower???

[lt1s10]

I thought the topic sounded interesting.

As for the axles, you could use some axles as lt1s10 put it, but you could also use your same old axles.

thats what i meant to say, "same old axles."

[SBC Maro]

My 355 Is making just under 400 at the crank, so I'm sure that as far as power goes, I should be fine.

So, I would probably order the Auburn (Was looking at that earlier) differential then? It says "3.08 and Up" Which I would assume means 3.08 and steeper ratios then?

Would something like that come with the gears already installed, and if so, how difficult is it to remove and reinstall the axles into the new differential? This should pop into my existing housing, no?

Thanks again, 'love learning about this stuff.

P.S.
I was trying to find a less suggestive topic title, but my imagination fell short.

[Dave Severson]

I've had good luck with the Auburn units. Normally you would buy the posi unit and gears separately, then you will have to either learn how to put the components in and set the ring and pinion to the proper clearances, or hire it done.....

As for the title, I don't see a thing wrong with talking about a nicely built rear end that is set up and maintained properly............

[SBC Maro]

Hah, sounds good. Thanks, Dave.

[lt1s10]

My 355 Is making just under 400 at the crank, so I'm sure that as far as power goes, I should be fine.

So, I would probably order the Auburn (Was looking at that earlier) differential then? It says "3.08 and Up" Which I would assume means 3.08 and steeper ratios then?

Would something like that come with the gears already installed, and if so, how difficult is it to remove and reinstall the axles into the new differential? This should pop into my existing housing, no?

Thanks again, 'love learning about this stuff.

P.S.
I was trying to find a less suggestive topic title, but my imagination fell short.

the carrier will come together, but its not gonna fall in the housing. you will have to install shims that pre load the carrier bearings and set your back lash. if you've never done this i would get some help.

[Dave Severson]

Might want to consider a set of C-clip eliminators, too. Them GM's make for a wild ride when one of the C-clips lets go.....guaranteed guardrail to guardrail excitement!!!!!!!

[Henry Rifle]

It says "3.08 and Up" Which I would assume means 3.08 and steeper ratios then?

Generally that's the case - but don't assume . . . verify. If you've never done a GM differential/ring/pinion install, I'd suggest having it hired out - or having an experienced friend help. There's one way to do it right, and about a hundred ways of doing it wrong.

I've had good luck with Randy's Ring & Pinon for obtaining parts. He has just about everything, and has a good website for hunting parts.

[SBC Maro]

Yea, I'll probably end up having someone with more experiance than me go for it.

Thanks again. Merry christmas!