Model A Ford Club of America
Sacramento, California Chapter

Mitchell Overdrive Gear-Splitter

The Missing Gear

Bonus Features of the Mitchell Overdrive (“Gear-Splitter”) - By Tim. Jones

Recently, in conversations with some of our members who have Mitchell Overdrives in their Model A’s, I was extolling the virtues of this product. (Technically, Mitchell Manufacturing refers to this product as a “Gear-Splitter”. Most owners just call it their “Mitchell”.) It became clear that some of the Mitchell owners were not aware of all of the ways their gear splitter can make driving a Model A, on today’s roads, a more pleasurable experience. One of our members suggested that I write something up and submit it to our Sacramento Capitol A’s newsletter, The Ahooga, so here goes.

A couple of years ago, Steve Mitchell and his mom, Sue, honored the Sacramento Capitol A’s by coming to Jeanne’s and my home for the monthly seminar, where the guys in the club installed our Mitchell Gear-Splitter. That day, Steve mentioned that we would probably like the high range second gear almost as much as the high range third gear. It took awhile to really become accustomed to using the “Mitchell”, but now that I am, I would never want to be without it. For those of you who have a Mitchell Overdrive in your Model A or may be considering installing one, there are some tips that you may not be aware of. But first I will take a minute to mention a few facts. The gear ratio coming out of your Model A transmission in third gear is 1 to 1. That is, for each revolution of your engine, you will have one revolution of your drive shaft. The Mitchell Overdrive comes with an assembly whereby the Mitchell is installed in the drive line. When shifted into high range, the number of revolutions coming out of your drive shaft is increased by either 26% or 36%, depending on which gear ratio you purchased. In Low range, it’s still 1 to 1.

Helpful tip #1. As everyone has noticed when driving a Model A, there is such a difference in the gear ratios between second and third gears that there almost seems to be a missing gear. This can be especially troublesome when going up even a slight hill in traffic. With the Mitchell, instead of shifting from second to third you can momentarily leave the transmission in second and shift the Mitchell instead into high range. This very nicely fills in that missing gear range. Now, here is where you need to pay attention. Your next shift is into third gear low range. That means that you need to shift both the transmission and the Mitchell. The best way is to first shift the transmission into third gear, because that requires double clutching, (because your Model A doesn’t have synchromech gears) and then I shift the Mitchell into low range. The Mitchell is equipped with synchromech gears so you don’t need to double clutch when shifting it. This may seem like more effort than it’s worth, but take my word for it, in those situations where you need to keep your rpm up, like going up a hill or getting onto a fast moving freeway, it’s worth it. Once you get good at it, no one even notices that you shifted two levers. You will find times in driving around town where second gear, high range is just right for the speed of the traffic. So play around and get comfortable with it. I’m sure you will want to use your new-found gear.

Helpful tip #2. Picture yourself at a red light waiting for it to turn green. When it changes, if you’re like me, you put in the clutch and grind your transmission into first gear, because remember, your Model A transmission doesn’t have synchromech gears. (Modern synchromech gears allow you to shift gears without grinding) With your Mitchell, when you get to the red light, put the transmission in first gear and put your MITCHELL in neutral and let out the clutch. Now when the light changes you can simply push in the clutch and shift the Mitchell into low range without grinding (because your Mitchell DOES have Synchromech gears. Sure, it’s more shifting, but what else were you going to do at that traffic light.

Helpful tip #3. Downshifting a Model A can be a real challenge for some drivers. With your Mitchell, it’s very simple. For example, when downshifting from third to second gear, push in the clutch and shift the Mitchell into neutral. With the clutch still depressed, you can now downshift your Model A transmission into second gear. Next, shift the Mitchell back into either high or low range, whichever is appropriate for the speed you are driving and let out the clutch. This same procedure can be used when shifting from second to first gear. All of this can be done without grinding the gears, or revving the engine, or double clutching. This sounds almost too good to be true.

And of course #4, the main reason you purchased your Mitchell, you will enjoy cruising the highways at speeds closer to that of modern cars, when you use the gear splitter in third gear high range. Steve, Cyndi or Sue Mitchell can help you decide which percent of gear splitter is best for your car.

Source: 
Tim Jones