Mitchell trasnsmission or overdrive?
- Thread starter wgmatt
- Start date
Tom Wesenberg
Well-known member
First get a 5.5 head for more power.
The 3.27 ring and pinion is another way to gain speed and at less cost.
The 3.27 ring and pinion is another way to gain speed and at less cost.
steve s
Well-known member
Do a search on overdrives. F-150 conversions are available. I like mine. 4-speed, only one lever.
Mitchell OD splits each gear into two ranges. Handy for pulling hills, but requires 2nd shift lever. Search for recent thread on one man's installment experience. Can be used with stock trans or with Mitchell trans in stock A box but modified with synchronizers and different gear ratio option.
Other options include a Volvo mod, Borg Warner mod, and GM 5-speed.
Mitchell OD splits each gear into two ranges. Handy for pulling hills, but requires 2nd shift lever. Search for recent thread on one man's installment experience. Can be used with stock trans or with Mitchell trans in stock A box but modified with synchronizers and different gear ratio option.
Other options include a Volvo mod, Borg Warner mod, and GM 5-speed.
Tom Endy
Well-known member
If you are looking to use your Model A for touring my advice is to purchase a Mitchell overdrive, they run around $2,300. It installs very easy and does not molest the Model A except for a slot that has to be cut in the floorboard and floor mat to accommodate the shift lever. You can always remove the overdrive and return the car to as it was and the overdrive has very good re-sale value. A Mitchell overdrive is 26% and can be used in every gear. Most often you would use it in high gear when you are above 45 mph. The overdrive does not increase the speed capability of the car it just allows you to travel at 55-60 mph with the engine rpm turning over like you were doing 45 mph. Second gear overdrive is very useful climbing or coming down steep grades. The 26% is designed to operate well with a 378:1 ring & pinion, which is the standard for a Model A.
The Mitchell transmission is about the same price and has the advantage of syncro gears in second and high so you do not have to double clutch. You can also get different gear ratios for second. Once you are in high the gearing is straight through as is a stock Model A transmission.
There are people who order both from Mitchell. Most often I hear people say they installed the Mitchell transmission so their wife could drive the car.
A Snyder 5.5 head as suggested above is also a good companion feature to the Mitchell overdrive.
Tom Endy
The Mitchell transmission is about the same price and has the advantage of syncro gears in second and high so you do not have to double clutch. You can also get different gear ratios for second. Once you are in high the gearing is straight through as is a stock Model A transmission.
There are people who order both from Mitchell. Most often I hear people say they installed the Mitchell transmission so their wife could drive the car.
A Snyder 5.5 head as suggested above is also a good companion feature to the Mitchell overdrive.
Tom Endy
modelAtony
Senior Member
Get the Mitchell , you can get different gears but the 26% is best. I have 5.9 brum head and 3;27 rear that I wouldn't trade for anything. My 31 tudor runs 60 mph at 1800 rpm. After you get use to the overdrive you can use it and all will be like everything is synchronized, you can go into first gear before you come to stop or keep rolling. I HAVE HAD THIS SET UP SINCE 2001-2003. CHECK MY INFO ON SITE. HAVE FUN MODELaTONY TONY WHITE lAFAYETTE, la
steve s
Well-known member
If I lived in hilly country and had it to do over again, I would get the Mitchell OD. There is a dead zone in Model A gearing between about 25 and 35 mph where it's too fast for 2nd and too slow for 3rd on moderate hills. The Mitchell OD in 2nd should fill this nicely.
However, living where I do in MI, I wouldn't trade my F-150 4-speed OD. Nothing to "get used to" and a whole world easier to get my wife to drive (which, if for no other reason, is a safety feature that we all should think about). My wife has never driven a stick shift before of any kind. BTW, I also have the Brumfield 5.9 head.
However, living where I do in MI, I wouldn't trade my F-150 4-speed OD. Nothing to "get used to" and a whole world easier to get my wife to drive (which, if for no other reason, is a safety feature that we all should think about). My wife has never driven a stick shift before of any kind. BTW, I also have the Brumfield 5.9 head.
nickair
Senior Member
Two options I like:
1) Seems to me that WITH the Mitchell Overdrive you would not need the Mitchell transmission with the modified gear ratios. The overdrive splits the gears to be more efficient with the engine and gives you an overdrive.
2) With 3.27 rear end gears I would do the modified gear Mitchell transmission and a higher compression head for more torque. The mods go on and on...
If I remember the torque peak is at 1200 rpm. From there the higher rpm goes the lower the torque goes. Point is that overdrive loves more torque to hold your speed. Seen guys that have an overdrive that doesn't get used much where there is the slightest incline. The other guys will have much to add to this.
1) Seems to me that WITH the Mitchell Overdrive you would not need the Mitchell transmission with the modified gear ratios. The overdrive splits the gears to be more efficient with the engine and gives you an overdrive.
2) With 3.27 rear end gears I would do the modified gear Mitchell transmission and a higher compression head for more torque. The mods go on and on...
If I remember the torque peak is at 1200 rpm. From there the higher rpm goes the lower the torque goes. Point is that overdrive loves more torque to hold your speed. Seen guys that have an overdrive that doesn't get used much where there is the slightest incline. The other guys will have much to add to this.
JohnLaVoy
Well-known member
I have been very pleased with the Mitchell overdrive. I've driven many thousands of miles and really appreciate the 2nd overdrive for climbing long hills. I have a borg warner on the phaeton and it served me well but doesn't work well in the hills. The regular Model A transmission has also worked fine for me over the years but that is a personal choice if you want the syncro trans to make it easier to shift.
Hoogah
Well-known member
Here are links to the two recent threads that I instigated, including the one mentioned by Steve S re my installation experience.
http://www.fordbarn.com/forum/showthread.php?t=142966
http://www.fordbarn.com/forum/showthread.php?t=144350&highlight=mitchell
Brother Hesekiel
Senior Member
Everything; 5-speed; $1,650
KenCoupe
Senior Member
I agree with Tom Endy and others on this thread about the Mitchell overdrive. I talked to Tom about the overdrive when he rebuilt my rear differential. I got the Mitchell overdrive and I have a 3.78:1 rear end and a 5.9 head. I couldn't be more pleased with the Mitchell overdrive. It works great. The second shift lever is not an issue for me; I can always take the overdrive unit out and go back to stock if I need to. Installation was not that difficult. A couple of guys from our club helped me install it. Our biggest obstacle was because my car has hydraulic brakes (I didn't know any better when I bought the car) and getting some of the Mitchell parts to fit around some of the hydraulic parts was a bit of a challenge, but nothing we couldn't get around.
tbirdtbird
BANNED
FYI if you want the Mitchell Overdrive there is a 3 month wait once you have put in your order...plan accordingly
Don't know about the wait time for the Mitchell ******.
I love my Mitchell!
Don't know about the wait time for the Mitchell ******.
I love my Mitchell!
TerryH
Well-known member
To further clarify pulling ability with the Mitchell in OD.......I have a Town Sedan, which is the heaviest passenger Model A, and I also have the Snyder 5.5 HC head. With that setup, I can pull modest hills when going 55 mph.....it definitely is not too tall of gearing when used with the stock 3.78 rear end, but like others, I would recommend adding a HC head. Many of the BW OD's are 33%, and that is too high in my opinion.
Pat Martone
Senior Member
I have the Mitchell Overdrive and am now "spoiled" and wouldn't want to drive a Model A without one.
I too, did not install it to drive really fast, but wanted to drive at 45-50 mph without the engine "screaming". I also use the 2nd gear Overdrive quite a bit when on a hill, where 2nd is too high (engine screaming) and 3rd would be lugging the engine.
A surprising additional benefit is that I use that Mitchell shifter a lot, to make downshifting easier. I simply put the Mitchell shifter in Neutral, then downshift without any gear grinding, before re-engaging the Mitchell. Another nice feature when stopped at a red light is to keep the Mitchell in Neutral and place the transmission in first gear, then it is an easy and grindless shift of the Mitchell into low gear to accelerate from a stop. I actually enjoy "playing" with both shifters.
I wonder if anyone else uses the Mitchell Overdrive as I do?
I too, did not install it to drive really fast, but wanted to drive at 45-50 mph without the engine "screaming". I also use the 2nd gear Overdrive quite a bit when on a hill, where 2nd is too high (engine screaming) and 3rd would be lugging the engine.
A surprising additional benefit is that I use that Mitchell shifter a lot, to make downshifting easier. I simply put the Mitchell shifter in Neutral, then downshift without any gear grinding, before re-engaging the Mitchell. Another nice feature when stopped at a red light is to keep the Mitchell in Neutral and place the transmission in first gear, then it is an easy and grindless shift of the Mitchell into low gear to accelerate from a stop. I actually enjoy "playing" with both shifters.
I wonder if anyone else uses the Mitchell Overdrive as I do?
Al 29Tudor
Well-known member
Brother Hesekiel,
Any details on a five speed? Over drive?
Type of ******, kit parts etc.
Sounds interesting - everything in one location with one shifter.
Thanks,
Al Leach
Jason in TX
Well-known member
I run the volvo overdrive on the bottom. Here is a photo showing the mitchel and the Volvo. Mitchell is mechanical lever on the floor. Volvo is an electrical switch hidden under the dash rail. flip of the index finger and you are in or out of overdrive in any forward gear.
