David DeCan

Looking to purchase a used Posi Carrier to swap into my 70 Cutlass Convertible peg leg "O" type 8.5 inch rear end. Also looking for gears. Will pay with PayPal. Text/Call/Email. 406-531-6939. david@daviddecan.com.
Thank you.

Fun71

Be aware that the O-Type has different posi carriers for different gear ratios.

Here is a list of the posi units & what gears they will fit:
#673 = 2.56 & 2.78 ratios, 28 spline
#671 = 3.08 & 3.23 ratios, 28 spline
#588 = 3.42 & anything numerically higher, 28 spline

This info is for factory gears; the aftermarket Richmond Gear (and other brands I think) ring and pinon gear sets are made to fit the 671 carrier. I think those came in 3.90 and 4.10 ratios only.

Also, there are aftermarket LSD units that are machined Ford 8.8 carriers, but I don't remember if they are made specifically for the 3.08-3.23 gear sets. Staying with the O-Type means your gear ratio choices are limited.


Any thoughts on what gear ratio you want? I saw in your other thread you were looking at a TH200-4R overdrive transmission, so I am guessing you don't want 2.56 gears.

lemoldsnut

This is very good information.

I could use one for 3:08

and a P type one for 3:23

If anyone has one of either of these let me know

Thanks
Larry

lemoldsnut@aol.com

or calls 8 am to 8 pm 541-815-4363

orange442

The aftermarket gears for O type 12 bolt are 3.42 and 3.91. 4.10 were discontinued several years ago.

oldsmobiledave

They are designed to fit the 3.08/3.23 carrier. I believe that Brian Trick has stated that the Richmond gears can be used in the 3.42/3.91 OEM carrier by planning .100" off them. Check with Brian for confirmation.

David DeCan

Looks like I am not the only one looking for one of these. Would also consider a Chevy 12 bolt posi. The cost for a new unit carrier is high. Any thoughts on this are appreciated. Brian Trick has offered a fair price on a new set-up to convert my peg leg. Also considering this. Thank you Brian. I am becoming convinced a used unit is long shot.

lemoldsnut

Yea I am gathering parts now for our next project. my 70 442. It has had many of the original parts changed out so a numbers match car it will never be. I wanted a driver car anyway so a very nice 455 and an M20 will be installed it now has an incorrect 12 bolt Chevy rearend. It is a peg leg and not a desireable ratio so I also have a few O type 12 bolts. I want something like 3:23 or 3:31 gears. So, what comes up with be what goes into it. I also have the 67 we are doing now and it has the P type with 3:90 gears and I won't be running that, we plan to go with either 3:55 posi which I have or a 12 bolt O type with 3:23 in it. This car is otherwise a numbers car. with the original 400 E type and an M20. I will save the original rearend for it to keep the numbers issue safe.

So, if anyone has either carrier I can use a P type and or an O type and for that matter a 12 bolt Chevy Carriers.

Thanks
Larry

Chesrown 67 OAI

You left out the most sought after type O posi units off your list -- the 672 - 31 spline for 3.42 or lower gears.