[joegpho]

With the recent resurgence of parts available for the 57-64 Olds/Pontiac rear ends can such a rear be put under a 65 Catalina?
I am curious as it is:
An interesting conversation piece - keeps it "Pontiac".
A stout unit.
Makes changing rear gears easier.

I am clueless on how springs and control arms would mount - also not sure of axle positioning and pinion angles.

Note - have 2.93 and 3.73 ratios for original rear, with the original posi unit.
If a car was to be raced, then the original rear can just be stored.

[hurryinhoosier62]

You could do it, but it would require a custom built Olds/Pontiac housing. Since Brad sold Fabcraft the number of parts available for the 9.3” Olds/Pontiac diffs have shrunk( gear sets especially) while the prices have increased dramatically. You might be better off contacting Quick Performance in Iowa and have them build you a custom 9” to fit your ‘65. That’s what I have decided to do with my ‘64 Cat.

[joegpho]

Thanks for posting - just a thought experiment.
If I really wanted to optimize the car in question for the drags - the Pure Stock Drags specifically - I should try to find a 4.11 gearset.

[AROWHED]

I went thru this adventure a few years back. There are a few hurdles to jump. https://forums.maxperformanceinc.com...d.php?t=824532

[mgarblik]

Originally Posted by joegpho

Thanks for posting - just a thought experiment.
If I really wanted to optimize the car in question for the drags - the Pure Stock Drags specifically - I should try to find a 4.11 gearset.

If your serious about the pure stock drags, be sure to very carefully dissect the rule book before making the investment. Different sanctioning bodies may require the same design rear end housing as the car came with. Meaning the drop out rears from the old Pontiacs or a Ford 9" would not be allowed. Only the Salisbury style that came in the 65-70 models. Good luck with the project.

[misterp266]

Originally Posted by hurryinhoosier62

. . . . . . .Since Brad sold Fabcraft the number of parts available for the 9.3” Olds/Pontiac diffs have shrunk( gear sets especially) while the prices have increased dramatically. . . . . . .

I noticed a lot less items on the website, didn’t know Brad sold it. Too bad.
Glad I got all my rear end and clutch linkage stuff already.

You can also put a 9” center section into a 9.3 Pontiac housing with a bit of work. Would then at least appear to be a true Pontiac rear.

[hurryinhoosier62]

Originally Posted by misterp266

I noticed a lot less items on the website, didn’t know Brad sold it. Too bad.
Glad I got all my rear end and clutch linkage stuff already.

You can also put a 9” center section into a 9.3 Pontiac housing with a bit of work. Would then at least appear to be a true Pontiac rear.

Brad sold Fabcraft about two years ago. Pricing went up, customer service went down. Brad was one of the “good guys” in the Pontiac world. Voluminous memory on all things 9.3.

[hurryinhoosier62]

Originally Posted by misterp266

I noticed a lot less items on the website, didn’t know Brad sold it. Too bad.
Glad I got all my rear end and clutch linkage stuff already.

You can also put a 9” center section into a 9.3 Pontiac housing with a bit of work. Would then at least appear to be a true Pontiac rear.

What has made up my mind on going with a 9” from Quick Performance is the cost( about $500 less than a Olds/Pontiac 9.3”) and gear selection. I’m going to run a 4L80E in my ‘64 Cat. According to Jake’s Performance I need a minimum of a 3.42:1 final drive gear ratio. Fabcraft’s 3.42:1 gear set is $400. The next set available is 3.64:1. With a 9” Ford you go 3.50/3.60/3.70. They cost half of what the Fabcraft 9.3 gear sets cost. Posi units run from $310 for a Track Lock street unit to $681 for a genuine Detroit Locker.

[joegpho]

Originally Posted by mgarblik

If your serious about the pure stock drags, be sure to very carefully dissect the rule book before making the investment. Different sanctioning bodies may require the same design rear end housing as the car came with. Meaning the drop out rears from the old Pontiacs or a Ford 9" would not be allowed. Only the Salisbury style that came in the 65-70 models. Good luck with the project.

Well - I've done the Pure Stock drags for quite a few years now.
The rules for the main one (at Mid-Michigan Motorplex in September) merely state:
The rear axle must be of the same manufacturer as the car. Any gear ratio is allowed.
Note they do not specify any year range.

I'm not racing the car in question - at least not anytime soon!
The thought now is that I would like to collect a 4.11 gearset for the existing rear.

[misterp266]

Originally Posted by joegpho

. . . . . . .
The thought now is that I would like to collect a 4.11 gearset for the existing rear.

Unobtainable.
When I raced my ‘66 GP years ago, the best I could find was 3.42’s. Brad used to have 3.55’s but no longer. Not even sure there ever was a 4.11 for that rear.
If it needs to stay Pontiac, use the 9.3. If not, go 9” Ford.

[tom s]

John at J&S gear in Huntington Beach CA bought the 9.3 deal from Brad.Tom

[Bill Hanlon]

Originally Posted by misterp266

Not even sure there ever was a 4.11 for that rear.

1966 Chassis Parts Book lists 4.11:1 and 4.33:1 gearsets for 65-66 big Pontiacs. Same book lists a 4.10:1 for the 64 rear axle.

And then there are these from the Pontiac Master Parts Catalog dated 10/1/60.

[mgarblik]

The OP states the rules require a GM rear end in a GM car, but don't specify a year range. That seems to leave the door open for the 9.3 Pontiac rear. Sounds like a ford 9" would not be allowed. I have installed a 3.42 and a 3.73 in the OE 65-70 full size housings. 4:11 and 4:30 I have never had my hands on although they were supposed to exist. Finding a set would be one heck of a find. Other than being very expensive to build, I like the 9.3" Pontiac rear. Stronger/Better than a Ford 9"? Personally, I don't think so. The extra support bearing on the pinion in a Ford 9" is a deflection game changer IMO. I do know the 9.3" cost more than twice as much as a Ford to rebuild with new parts. I recently replaced the limited slip unit, ring and pinion 3.42:1 and bearings and gaskets in my 9.3. About $1700.00 in parts from Fabcraft. I appreciate that they are still in business and have the parts, but they are expensive if your on a budget.

[Richie Hoffman]

shop i work at we put a 12 bolt chevy in a 65 catalina we pull the tubes out of both rears and put tubes from catalina rear in a12 bolt center

[mgarblik]

That's interesting. So you use the center section out of a Chevy A body? I ask this because the B body Chevy 12 bolt doesn't have attachment points for the upper control arms? They use a panhard rod, don't they? That would make a strong, almost stock looking axle.