4 Speed w/o Overdrive

Volvo/Laycock OD types were installed in the torque tubes for model A overdrive set ups some years ago. The Borg Warner R10 ODs were as well back in the 60s & 70s with some in the 80s. The Mitchell ODs are the current ODs. The Mitchell model A transmission mod makes a semi-synchronized transmission using the model A case but it's only the usual 3-speed. Shifts like the later 91A type Ford 3-speed.

Installing a later type 4 or 5-speed is a complicated process and in many cases it changes the location of the shift tower farther to the rear. It's just the nature of the beast. A fellow on the early V8 side used a truck shift tower bolted to the top of an old Mercury R10 open drive type side shift transmission to get a top shift 3-speed with electric OD. It was an interesting shift mechanism but it works. A person could likely do this with an early Ford T-10 side loader if they wanted to but it would take some engineering for sure.
 
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Genebob, the Volvo gearbox is called a M40, it’s very short, but strong enough to handle a model A 4 cyl. If you can or know somebody who can machine an adapter, you can keep the torque tube stock size. This simplifies the conversion, there’s no pedal shaft on the AA bellhousing, so that has to be fabricated, and the flywheel modified to mount a Volvo clutch plate.
 
Skip65, Thank you for pointing to the correct Volvo 4 speed. I will look online for one of these occasionally. Didn't see any on my first search.
 
Thank you all for the information. This is not a current project, just gathering information for a "someday" possibility.
 
GeneBob said:
Thank you all for the information. This is not a current project, just gathering information for a "someday" possibility.
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Just remember, anything can be adapted to any car but the FIRST thing to be considered should be the available ratios. Those need to be tailored to the engine and the way the car will be used. Ratiowise a close ratio T10 would be ideal. A wide ratio T10 would not. Some of the very popular conversions have very poor ratios for street use. The type of rear end is a big consideration also.
A little known fact. Some adapters can be made with nothing more than a drill press and a hand jig saw.
 
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