4 speed gearbox advice needed.
 

Does anyone know of a period (pre1940) 4 speed gearbox that would be suitable for a model a Ford race car. It needs to be quite compact as it’s a single seater with limited room. Length isn’t too much of an issue but it can’t be too much wider than a standard model a box. A AA gearbox isn’t any good as 1st will be too short.

Re: 4 speed gearbox advice needed.
 

"Suitable" covers a multitude of sins. Are there British cars that would have had a box matched to a 3.3 liter engine? Something like that would be easier for you to find. Machining one-off adapters would be a challenge.

Re: 4 speed gearbox advice needed.
 

The problem is also the power delivery as it’s for a Rutherford head engine so a bit more go than a standard model a.

Re: 4 speed gearbox advice needed.
 

Four speed gearboxes were only used in trucks prior to the late 1950s when the T10 came out. They are huge, plus most are non synchronized. The only option would be the Mercury R10 overdrive transmissions of 1949 through early 1951 with a top shift adapter installed. One of our members (expavr) did this with success. There are posts about it on this forum. The other option is the Columbia overdrive or a modern torque tube overdrive like the Mitchell overdrive unit. The older R10 and Laycock types are still around to some extent and they are electric where as the Mitchell is lever operated.

Re: 4 speed gearbox advice needed.
 

Vince Falter at his fordgarage.com site has outlined extensive information about later model "substitute" transmissions for the Model A Ford. IIRC, about five are "adaptable" but one or two of the less frequently found ARE THE ONES BEST SUITED.

You can start at https://www.fordgarage.com/pages/TremecT170FT.htm


Joe K

Re: 4 speed gearbox advice needed.
 

Guys he's asking for pre 1940 4speeds because Vintage Racing in England is very fussy about using period pieces.
Pauly 1, 1959 was the first year for a passenger car 4 speed on this side of the Pond.
If I was you I would think about maybe using a Mitchell converted Model A Transmission with a custom gear ratio to suit for the first 3 gears then adapt a Model T KC Warford transmission with an Overdrive gear to get your 4th speed.
Just thinkin

Re: 4 speed gearbox advice needed.
 

I think Ruckstell made rear ends for Model A's, but since they were not needed they did not sell well. I might be wrong.

Re: 4 speed gearbox advice needed.
 

Actually Corvette first had a four speed in 1957.

Re: 4 speed gearbox advice needed.
 

Volvo had a 4 speed manual (M4) in the 1940s.
http://www.nuceng.ca/bill/volvo/database/tranny.htm

Re: 4 speed gearbox advice needed.
 

The Ruckstell units are e tremely rare that were made for model As.

Re: 4 speed gearbox advice needed.
 

Duesenberg had originally put a 4 speed in the Model J in 1928, but since the engine had so much torque it would blow itself to pieces, so they removed every 4 speed and put 3 speed transmissions in them. the Duesey 3 speed is suspiciously similar in design to an A transmission...

Re: 4 speed gearbox advice needed.
 

This last weekend I saw a 1940 Ford sedan with a Columbia overdrive rear end. If I remember correctly it came out of an early Mercury.

Re: 4 speed gearbox advice needed.
 

Try 1930 Chrysler 77. It had a 4 speed

Re: 4 speed gearbox advice needed.
 

The last one that sold on Ebay sold for north of $5K.

At that price and rarity one might be foolish to actually install it in a working car.

Does anyone currently produce a Columbia or Ruckstell type overdrive for the Model A? Not talking about Mitchell Tranny or Torque tube.

Joe K

Re: 4 speed gearbox advice needed.
 

I believe I would go in a different direction. The Rutherford head can be tuned with a cam change to have decent mid-range torque. My first choice would be to use a Mitchell synchromesh transmission inside of a stock Model-A case, ...or I would use a '39. Some of the early 4 speed 'crashboxes' could not be speed-shifted effectively. Changing gears takes time. Having an engine with a proper camshaft that has a strong midrange thru top-end backed by a quick-shifting 3 speed will be faster than a typical 4 speed.