67 Catalina

67cat
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67 Catalina

Postby 67cat » Mon Apr 30, 2018 8:59 pm

Hi Jim
My name is Eric, I have a 1967 Catalina. After doing a lot of research I have found your site to be the most informative about this oddball 12 bolt rearend with a 10 bolt cover. I also have 67 Pontiac service manual which also helped me to decipher the gear ratio to be a 2.56 open carrier.
My question is, are there any 12 bolt Chevy rearends that have the same wheel base that will bolt in? Like maybe an impala or chevelle rearend, something a little more commonplace or possibly a mid 70's 8.2 BOP from a wagon or full size?
I would like to go with a 3:31 or 3:42 and keep my original rearend intact as original.

Thanks, Eric

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monzaz
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Location: RICHFIELD, OH

Re: 67 Catalina

Postby monzaz » Tue May 01, 2018 7:20 am

Eric, As always ...bad news? Full size car rears from 1965-1976 are all on their own .
Your stuck with what you have or you will need to pay for a CUSTOM rear. The upper control arm mounts are the hardest thing to get around and cause all the issues of an interchange.
We had Ideas of making custom rears for the full size cars...BUT time and actual amount of rears we would sell just does nt seem to make it possible to do.
We did have 3.55 gears and we still have posi units on the shelf to make your 65-76 10 bolt cover 12 bolt gut (Pontiac 8.875) rear spin two wheel with better ratio.
At this time we have one set left of the 3.55 gears - they are from Fab craft metalworks and they only make 30 sets every so often ...they have not made any in about 2-3 years now...

So that is it for now. If you have a welder I am sure you can make anything fit some what...

Jim
J D Race
J D Race

67cat
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Posts: 8
Joined: Mon Apr 30, 2018 6:47 pm
Location: Mooresville, nc

Re: 67 Catalina

Postby 67cat » Tue May 01, 2018 10:43 am

Well son of a peach basket!
I do have a mig welder and a 69 chevelle 12 bolt peg leg! Guess I'll get the tape measure out and check the width. Only thing is 5 on 5 full size vs 5 on 4.75 means new rims!

How much for the 3.55 and posi?
Would the 3.55 work with my open 2.56 carrier?

I love this passed over oddball Pontiac but parts are hard to find! :shock:

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monzaz
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Re: 67 Catalina

Postby monzaz » Wed May 02, 2018 7:32 am

Well back in the day THIS Pontiac rear was the rear to have. They did support the rear from the factory with speed parts. BUT it is going on the 52 year old mark now - Catalina 2+2 were the race cars in the day.
they had 4.33 3.90 3.73 gears for this rear and they are out there still just they are hidden because no one knows what they are when they are loose and in a box at a swap meet...lol.

Again you can probably fit any rear under the car ...but getting it right is the key.
Custom axles can be made for ANY 12 bolt Chevy so that is really not an issue. drums can be redrilled or I think 787980 caddy seville had 9.5 x 2 5 on 5 drums.
You will need to make custom upper control arms to fit the 66 cat chassis to the 12 bolt chevy upper control arm ears.

3.55 will fit in any 1965-1976 Pontiac FULL SIZE rear. you will need a correct carrier also. 3 series. (we might have a few of those too. )
Jim
J D Race


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