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-   -   Is this an 8.2 or 8.5 rear (https://forums.maxperformanceinc.com/forums/showthread.php?t=868718)

grivera 08-21-2023 02:40 PM

Is this an 8.2 or 8.5 rear
 
2 Attachment(s)
At work right now so limited to the pictures on my phone. I hope to get more pics tomorrow. Based on these pictures of the rear in my 69 Lemans, is anyone able to tell if it’s the original 8.2 or an 8.5? BTW, it has 4.33: gears

hurryinhoosier62 08-21-2023 02:42 PM

Judging by the cover, an 8.2.

steve25 08-21-2023 04:09 PM

8.2.

grivera 08-21-2023 04:16 PM

Thank you. At some point I’ll have to decide on what to do with the rear. Right now I want to make the car reliable so that when it’s time for bodywork it is mobile/moveable under its own power. I’m not ruling out building my spare 455 block and using my spare set of 310 85cc KRE heads, but that is long term. If I go that route will need a stout rear.

If the current #s matching 350 proves to be solid I have no issue cruising and enjoying it. This will lead to a decision point of put street gears in the 8.2 or get a stout rear for what may come down the road…

b-man 08-21-2023 04:20 PM

Well at least you can swap in some more street friendly 3.36 gears if you decide to keep that rear end, that’s the lowest gear set numerically that will fit your posi unit.

You’re gonna really hate driving around with 4.33s before long.

sdbob 08-21-2023 05:01 PM

It can be a rush on street tires! Esp going into 2nd gear.

Formulas 08-21-2023 05:08 PM

Quote:

Originally Posted by sdbob (Post 6449230)
It can be a rush on street tires! Esp going into 2nd gear.


most people focus on the negative there is however the other side of the coin, when it comes to deep gears 4.11 to 4.56 and a 3.75 stroke they can be alot of fun as well

also 4.33 isnt as common of a ratio and if its a OE gear can have some resale value there isnt very many available either new or old

I have a 1970 8.2 F-body 3.36 posi and its the 2 piece carrier with cones
yours appears to be a 1 piece unit is that because of bolt in axels vrs C'clips?

PunchT37 08-21-2023 05:27 PM

Let’s not forget Dairy Queen. ;)

grivera 08-21-2023 05:37 PM

2 Attachment(s)
Quote:

Originally Posted by Formulas (Post 6449231)
most people focus on the negative there is however the other side of the coin, when it comes to deep gears 4.11 to 4.56 and a 3.75 stroke they can be alot of fun as well

also 4.33 isnt as common of a ratio and if its a OE gear can have some resale value there isnt very many available either new or old

I have a 1970 8.2 F-body 3.36 posi and its the 2 piece carrier with cones
yours appears to be a 1 piece unit is that because of bolt in axels vrs C'clips?

I'll have to investigate - it has the SSBC rear disc conversion which I'll be cleaning and lubing so will take a peek

blueghoast 08-23-2023 12:59 AM

I wanna know how that thing go's geter done, Please

GT

HWYSTR455 08-23-2023 11:25 AM

Personal opinion, always build best/better/bigger/beefier. Even if the car never reaches the point to take advantage of it, you KNOW you will never have to worry or do it again. If you do a 'get-by' fix, the money/effort will be wasted in the long run.

I wish I wouldn't have built the 8.5 in the 442, and just gone straight to a Moser 12. I never expected to do a stroker engine for that car, but it fell in my lap. For another $550 over the cost of doing the 8.5, I would have had that Moser. And now it needs it.


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242177P 08-23-2023 04:28 PM

Judging by it's cover...
 
You cannot judge an 8.5 by it's cover. There were a couple of covers used, and the one I have (71 Cutlass, bolt in axles) uses the 8.2 cover. Ol' Pinion Head made some sneaky ones, take a grinder to the square lugs. A step in the side profile will give it away.

Where the brake line bracket is mounted, does it use the 12 o'clock cover bolt (8.2), or is there a cast provision for it (8.5) on top? Casting number?

grivera 08-23-2023 04:55 PM

2 Attachment(s)
Quote:

Originally Posted by b-man (Post 6449220)
Well at least you can swap in some more street friendly 3.36 gears if you decide to keep that rear end, that’s the lowest gear set numerically that will fit your posi unit.

You’re gonna really hate driving around with 4.33s before long.

The 3.36s are definitely a step in then right direction, especially with taller tires. Here is a decent Yukon set: https://www.ebay.com/itm/33484065899...3ABFBMtuDdwsRi


Quote:

Originally Posted by 242177P (Post 6449706)
You cannot judge an 8.5 by it's cover. There were a couple of covers used, and the one I have (71 Cutlass, bolt in axles) uses the 8.2 cover. Ol' Pinion Head made some sneaky ones, take a grinder to the square lugs. A step in the side profile will give it away.

Where the brake line bracket is mounted, does it use the 12 o'clock cover bolt (8.2), or is there a cast provision for it (8.5) on top? Casting number?

The brake line bracket uses the 12 o'clock bolt

Held for Ransom 08-23-2023 05:24 PM

9795082 is a 1969 rear made using gray iron, not as strong as the 9795084 nodular iron unit.

grivera 08-23-2023 05:54 PM

Thank you!

HWYSTR455 08-23-2023 07:08 PM

Quote:

Originally Posted by 242177P (Post 6449706)
You cannot judge an 8.5 by it's cover. There were a couple of covers used, and the one I have (71 Cutlass, bolt in axles) uses the 8.2 cover. Ol' Pinion Head made some sneaky ones, take a grinder to the square lugs. A step in the side profile will give it away.

Where the brake line bracket is mounted, does it use the 12 o'clock cover bolt (8.2), or is there a cast provision for it (8.5) on top? Casting number?

Yup, the 442 is a bolt-in 8.5. Finding the right axle bearings can be a challenge.


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grivera 08-25-2023 09:41 PM

1 Attachment(s)
Is it an Eaton style or Cone?

1968GTO421 08-27-2023 02:30 PM

Your question interested me so I went hunting on-line. I found this and think it answers your question if you look through the whole thing like I did. Hopefully it will be of help. (I personally think you have a detroit true trac on page 14 but review and see what you think.)

https://www.eaton.com/ecm/groups/pub...ct_3167716.pdf

Held for Ransom 08-27-2023 03:48 PM

Quote:

Originally Posted by grivera (Post 6450276)
Is it an Eaton style or Cone?


Auburn unit. https://justdifferentials.com/auburn...ntiac-8-2.html
Oh, and it's a cone style... https://auburngeardiffs.com/cone-clu...differentials/
Or, OE 2 pinion https://forums.maxperformanceinc.com...d.php?t=823573

Tom Vaught 08-27-2023 04:53 PM

9" Moser is SO MUCH EASIER, LOL!

Tom V.


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