Olds/Pontiac Rear vs 9" Ford

I'm in the parts collecting stage of my '57 Chevy gasser project, and someone else's thread about which rear to go with got me thinking. I know there is a strong preference for the Olds/Pontiac rears, and I know they are much stronger than the original Chevy rears and "look" right in these cars...but what about the 9"? I understand that in the late 50s-early 60s, the Olds rears were more plentiful, and an easier swap (bolts in with factory leaf spring mounts, right?), but for a late '60s-early 70s build (yeah, maybe slightly OT) weren't the 9" rears becoming more common in these cars? And with a nodular case, and 31 spline axles, wouldn't the 9" be stronger? I haven't ruled out the Olds, but could someone tell me any advantages it may have? I can't imagine that parts for it will be any cheaper than 9" stuff.

 

Advantage Olds --> Looks Cooler
Disadvantages --> Harder to get parts for
I assume "stock" strength may be similar, but ends there as there are LOTS of upgrades available for the 9"

 

I think the ring and pinion are larger (..9 3/8" I believe) as is the axle diameter in stock form. I know they make 40 spline 9" now.

The Olds and Pontiac are super stout and don't rule out the Buick of the same years. They are not interchangeable with the Olds and Pontiac but are pretty much the same. I have a Buick rear from a '61 Electra and I have to say that in shear size the Buick is much larger than any 9" housing made. It was designed to handle 455 LBS of torque from the factory which is a lot. Not sure what Ford product built back then had that much.


Good luck with you decision.




BloodyKnuckles

 

Depending on your horsepower you may not need a Nodular case. However going with a Nodular case, good quality 31 spline axles (ex. Moser Engineering), good quality gears (ex. Richmond Pro gears) and don't forget a "Daytona" pinion support as well as a billet yoke will be fairly bullit-proof capable of handling desent horsepower numbers. Also keep in mind that if you plan on racing your car, NHRA and IHRA rules make it "MANDATORY" that you only use aftermarket axles. Parts for the Ford 9" will definitely be cheaper as well as easier to get than the Olds/Pontiac rear just because there's more demand for the Ford 9".

 

That just might be the clincher, as I am going to build this car to pass tech, even though its going to be driven more than its going to be raced. I'm planning on beefing the 9" up a lot (probably just order an assembled centersection from Moser with all the above), since the car in question is getting a tunnel rammed big block. Since this car is going to be driven long distances (Power Tour, HAMB Drags, etc), the 9" may be a better way to go...at least if I break it, spares will be easier to get.

 

Yea, the spare parts are something else to consider. Also don't just rush out and dump a load of cash on an assembly before looking around. I put together my big bearing Nodular center section with Daytona pinion support, Strange spool, Ford Racing gears, complete master rebuild kit and the labor to set it all up for a total of $510.00 plus the axles. I did it all from swap meets, Craigslist, the internet and I know a guy that specializes in setting up gears. It just took a little time to save a boat-load of cash! And I think it works too!!!! Don't you think?

 

Ive got a 57 chevy with a 9 inch ford. 425 hp no complaints here

I went/ am going with a 60's-70's period correct build

 

The round back 9 inch Ford looks a LOT like the original rear end ...



Parts are less expensive and way more plentiful. Aftermarket support is unsurpassed. I would go with the Ford

 

depends how traditional you wish to be. also, the 9" takes more power. Just try rolling a car with a 9" and then roll a similar weight car with almost anything else. Has to due to the configuration and where the pinion enters the case. See above photo.

I am a big fan of the Olds and feel they are tough and traditional.

If you are starting from scratch, contact Brad at Fabcraft in Texas. He is extremely knowledgeable and will be able to tell you what investment you will make in the Olds. Then cost compare with the 9" ford.

In the end, you will NEVER have to apologize or make excuses as to why you chose the Olds.

just my $.02

 

Go with the olds its old school!!!

 

If I could build one for close to the same price, and have it be just as dependable (I have no doubt it will hold the HP), I'd do it. Thanks for the info, I'll check with Brad.

I have heard the same thing on the power takend to drive a 9", but in practice (on the dyno) I have seen very little difference between "efficient" rearends like the 12 bolt Chevy, and the 9". As long as it doesn't break, I don't mind a little extra HP being used. I wouldn't think the Olds rear is any more efficient anyway.

 

If you're going mid 60s/early 70s you've left out the most popular rearend-12 bolt Chevy. They're stout enough and pull less horsepower. Good enough that the Hemi Super Stockers ran them for a while.
9" Fords are stout when you build them with upgraded parts, but I've seen more than one in a drag car sitting there with the driveshaft flopping around with the pinion still bolted to the end of it. I think a good pinion support would be my first upgrade.
Now in case you think I'm prejudice, I've got two different projects that I've narrowed 9" Fords for. But my Old Anglia is getting the Olds replaced with a narrowed 12 bolt.
Larry T

 

I've sold rears to Brad. Hell of a nice guy, got good stuff but certainly not cheap!
And the GM 12 Bolt has weak axle tubes, this is fact!
Just my $.02 + experiance

 

There is a Ford 9" diff housing available that uses GM gears.

The Ford diffs are pretty tough. I think broken ones are more about how much traction and power a car has rather than how weak the 9" Ford is. But either way, you are right, good parts makes them tougher.

 

I am an olds guy but truth be told $ says the 9 inch is the best bang for the money.

 

I left that one out for a reason; I'm just not a fan. I have put in many 9" rears to replace broken 12 bolts (for customers), but never the other way around. If I was going to use anything but a 9" or Olds, it would be a Dana 60. I only use 12 bolts for restorations, or if the customer insists (brand loyalty).

 

I usually weld the axle tubes to the center section and I'm gonna get Mark Williams billet caps installed on the 12 bolt.
Like I said, I've got 2 cars sitting here with 9" Fords in them, but they have Strange nodular cases and Daytona pinion supports in them. Not a real cheap way to go either.
Larry T

 

I' m in the same delima with a 55 old school Gasser I'm building and I believe I'll go with a Ford 9 inch. While on this subject hows about the Mopar 8 and 3/4 rears for such applications. I know a lot of guys ran them in Super stock and Stock classes back in the day. yruhot

 

The Ford 9" has the extra bearing on the end of the pinion that adds tremendous amount of strength and reliability. That is right where the power changes directions. The Ford 9" is the current axle of choice and there is very good reason.

If the Olds/Pont was so good, you would still be able to get everything for them yet today and it would be plentiful and cheap. I had a Big Block Vega drag car that had an Olds/Pont in it. Weighed about 2400 lbs and went High 8s and low 9s. Broke the rear about 3 times. Only really 2 ring and pinion ratio choices out there (4.10 and 4.88) and Richmond is the only game in town. After I broke it for the 3rd time in two years, I sold it to some nostalgia racers (It had all Strange parts in it) and got enough money to almost pay for the 9". Sold the car about 6 years later and the 9" ring and pinion still looked like new. I didn't change anything else in the car but the rear and never had another issue.

Nobody will convince me that the 9" is NOT the way to go. Spend the money, do it right, and forget about it. It will be way cheaper in the long run.

 

for wt watchers the O/P is heavier.

 

I ran a shortened 64 Pontiac rear in my 550 HP 63 Tempest, ONLY because I was trying to be "period correct". Beat the hell out of it and it never skipped a beat. However, it cost me a FORTUNE to build the same rear end I could have gotten for a LOT less if it were a 9". Parts availability for these rears is no where near what is available for the Ford 9". Back in the 60's/ early 70's the Olds rears were the thing to do. But as parts became scarcer for the Olds/Pontiac and parts/development for the 9's started picking up, the Ford 9" took over. I'd stick with the 9"...

 

Just a bit of info for those who do not know, but a Chrysler 9 1/4 posi will bolt into a olds pontiac carrier, they are quite cheap for a new one. My buddy Rex ran that posi in this 55 with the op rear.

 

9 1/4 mopar?..lol..many parts are interchangeable..i prefer the 57-64 O/P and have never gutted one..i have period correct housings for you 55-57 guys..pm me..

the 9 inch soaks up power..its only true blessing is the launch..the pinion resists deflection because of the extra bearing..but its low set against the ring takes hp away..its a proven fact..

if you know the right folks, the O/P is not expensive to build..

the 9 inch ford was designed for dump trucks..really..

 

IMO, The Ford 9 inch is the small block Chevy of rear ends. Cheap at entry level, unbelievable oe & aftermarket parts availability and they can be built about as strong as your finances will permit. I don't really like sbc's but I have one. Got three 9 inch rear hot rods.

 

For me, am building a 63 Pontiac rear end ( Olds and Pontiac use the same parts ) using parts from Brad at Fabcraft for my blown altered wheelbase and slightly streched '65 Tempest. It will see some street use too.



He sells a housing brace, has 3, 4 and 5 series gears now so there are plenty of options on gear choice. Stock rears use 31 splines already, he sells 33 spline POSI and also has spools in both 31 and 35 spline.

Fabcraft Metalworks 800-208-8242 www.fabcraftmetalworks.com

 

Yes the extra pinion bearing is there to add extra support, but not for the reasons some may beleive. The position of the pinion to the CL of the ring gear puts alot of stress on the pinion and thats why the third bearing. This also causes extra drag and eats up a lil horse power. My thought is stay old school and go Olds/Pont..

 

Buick was closed driveline thru 59 or 60 where the Olds an Pontiac used a driveshaft. The Olds and Poncho rears were the most common after guys got tired of blowing up stockers.

Mark Williams still stocks upgrade parts as well.

 

Sorry. I forgot about the closed driveline thing. If you can find an open Buick they are super stout but parts are pretty scarce for sure.

Thanks for the clarification Tman.




BloodyKnuckles

 

They were a good, strong part but it's a matter of supply and demand...the thing is, GM stopped building them in 1964 while Ford continued with the 9" for another 15 or 20 years. The Ford diff was simply more common and easier to find, so it made more sense for the aftermarket to support it instead of the GM part.

 

Do you know who make those parts for M/W? Shhh, it is a secret.