Transmission / Overdrive: o.d. trans info wanted

[dstude]

This will probably be an easy question for someone. I'm assuming the overdrive transmission for a '51 Champion flathead six is different than the o.d. trans for that same car with a V8. Is that correct? Can someone tell me what the Borg-Warner model number (T-??) is for the transmission for the six and what it is for the V8. I'd like to swap a V8 into my '51 and I'm curious if the o.d. trans used by the six would be alright to use with the V8 (which will be a 259 from a '57 parts truck) Thanks.

[gordr]

The Champion six used the model T-96 transmission, which can be recognized by its 4-bolt top cover. The Commander V8 (and previous Commander sixes) used the model T-86 transmission, which is larger, has a different input shaft and front mount bolt layout, and has a six-bolt top cover. The only parts commonality between the two transmissions are the internal parts for the R-10 overdrive, which both transmissions use, if equipped with overdrive. Find a '55 to '57 V8 car bellhousing and overdrive transmission, and dial-indicate the bellhousing to your engine block to ensure it's concentric with the crankshaft. You might be able to make the truck bellhousing work, not certain.

[studeclunker]

You will need a car bellhousing and T-86 tranny for your Champion. Your Driveshaft will also need adjusting. Additionally, you will need to convert your brakes as the Champion brakes won't be able to handle the weight and power of the V8.

[StudeRich]

Ditto what studeclunker said, plus you will want a Commander V8 Dana Model 44, rear Axle to replace the lighter Model 23.

[dstude]

Thanks for the help. Though I haven't been under the truck to check, the V8 parts truck has a o.d. trans. Can I pretty safely assume it will be a T-86? The option would be a T-5 five-speed to get the o.d. Is that a practical option for a Stude V8? Are there adapters for that combo or does it require machining the bellhousing? Thanks.

[dstude]

Thanks for your input. My '57 parts truck has an o.d. trans, so I'm assuming it would be a T-86. Would you agree that is likely? I've also seen that there is a disc brake conversion for '51s with five-lug wheels. Would that solve a lot of the braking problems? Even with the six, braking is not the car's strong point.

Do you know, is a T-5 trans an option with a 259? Are there adapters or is it a matter of machining the bellhousing or is it a bolt-in?

[dstude]

Thanks for mentioning that. Do you know if the Commander model 44 housings are similar in width to the model 23s, or would they have to be narrowed? Any idea of other housings that might be the right size among Ford and MoPar rear ends? I'm not enough of a purist that I would hesitate to use another housing, especially since it might offer the option of having rear disc brakes. Thanks again.

[gordr]

Your parts truck will have, or should have, a T-89 transmission in it. Outwardly similar to the T-86, but it has different ratios, and also straight-cut (i.e. noisy) gears for low and reverse. You could use it, but it will drive like a truck did, back in the day. Now, a previous owner of the truck might have installed a T-86 overdrive transmission from a Commander car to replace a straight 3-speed T-89 that the truck came with. That was a popular swap, so you will have to check.

Model 44, model 23, and model 27 axles are the same width, center bolt to center bolt, on all cars '51 and up. Pickups are different. And U-bolts and the axle retainer plates/lower shock mounts have to match the axle, owing to different diameter axle tubes. If you change up to a Model 44, the rear driveshaft will have to be shortened.

The Ford 8.5 inch is becoming a popular swap.

[dstude]

Thanks. Excellent information.