View Full Version : GH 352 W/Ultramatic Rear End Ratio?

345 DeSoto
10-16-2015, 11:05 AM
Is there a "Standard" rear end gear ratio that came with the 352/Ultramatic in the '56 GH? I'm thinking of converting the Ultramatic to a 200 4R if it needs repair. Ideally I'd like a 3.73 T/T (if there IS such an animal) with the 200 4R. How about weight? What do each of these 2 transmissions weigh?...

10-16-2015, 12:22 PM
If you had an 3 speed and overdrive the ratio would be 3.92 to 1. I believe the ultramatic came wit a 3.07 to 1. The Packard V8 really doesn't start to come into it's own until you start to hit 2,000 plus rpm. These V8's were torque generators to move 2 plus ton cars but they were driven by the typical Packard owner at say a more "dignified" pace. With the 3.07 combined with the weight of less than 2 tons, the Golden Hawk would hit an honest 130 mph and still have room to go. I am sure that Studebaker Packard would not recommend doing that. I don't know if ever a Golden Hawk was taken to Bonneville but it would be interesting reading if they did. Hopefully, the hood would be more secure than just the stock set up, which was known to come unlatched sometimes.

Bob Miles
Tucson AZ

10-16-2015, 12:26 PM
Maybe the GM guys could chime in but I think the 200 4R would not be strong enough to put behind the Packard V8. Probably the 700 4R would be better. The 55 Ultramatic was cast iron, the 56 Ultramatic was Aluminum case and weight was about 100 pounds less than the 55. Don't know the weight.

There are kits available for the Ultramatic to help with some of the issues of the transmission.

Hope this helps some but there are better experts to chime in and help.

Bob Miles
Tucson AZ

345 DeSoto
10-16-2015, 12:53 PM
I had a beefed 200 4R in my last car that I built, and it held up just fine...11.88 in the 1/4. They need to be built for the added "strain"...

10-16-2015, 01:26 PM
Agree, the 3.73 with the 200-4R would make a really nice combination.

The Packard V8 torque curve is relatively flat and highest from 2,000 - 4.500 RPMs. but it makes more than 300 lbs/ft from 1500 - 5,000 RPMs.

Yes, you'll definitely want TwinTraction; also, from experience:

1. Flanged axles, traction bars, front and rear heavy duty sway bar, heavy duty shocks front and rear. If the stock wheelcover look is desired, 6" Ford or Mopar steel wheels. I'm running 8" custom Halibrands front and rear.

2. Move the battery to the trunk.

3. Electronic ignition trigger. Setting point dwell on a '56J is not easy or fun.

4. Most of the exhaust manifold gaskets which come in gasket sets today are junk and will burn out. I surface the manifolds and run without gaskets.

jack vines

345 DeSoto
10-16-2015, 02:03 PM
Jack - Talk to me about "flanged axles". The GH axles are tapered...correct?

10-16-2015, 03:20 PM
Jack - Talk to me about "flanged axles". The GH axles are tapered...correct?

Yes, 99.9% of all Stude axles are tapered and now more than fifty years old. You need the flanged axles. Fairborn has the kit.

jack vines

10-16-2015, 03:26 PM
Don't know about automatics, but as mentioned, OD cars came with 3:92s with a number of ratios optional - see attached sales letter.


345 DeSoto
10-16-2015, 04:27 PM
Thanks, Jack...

10-16-2015, 09:42 PM
When the Chevie Monte Carlo SS's came from the factory they were equipped with the 200R4 trannies and a 3.73 rear axle.. We seldom had a problem.. Must have convinced GM of their reliability as they also came in Buick's Gran National hot rod.. The 200R4's were more reliable than were the 700R4's back then..

10-16-2015, 09:48 PM

You can get a 700r4 adapter from these fine folks.
If you need wiring, I know someone with a new harness.
It's from Rhode Island wiring, none better.