Hi-speed ring & pinion vs overdrive

gilitos

Senior Member
The price of the Mitchell overdrive units is enough to make one pause and think carefully. I'm wondering if anyone has had experience with a high speed ring and pinion as an option. The 3.54 ring & pinion is 6.3% over stock, the 3.27 is 13.5% over, and the Mitchell OD is 26% over. The A is certainly geared low, and might do fine with modern driving conditions with a higher ratio differential. Has anyone put in a high speed ring and pinion and regretted it?
 
I installed the 3.54 in Ole Willie. It did fine in the hills around Birmingham. My engine is fairly strong. I have to wonder how the 3.27 would do.
 
Very good question, I dont see why it wouldnt work and improve alot of things. Other than the fact that the "A" engine does not do well with "lugging" along at low RPMS, it is actually worse than revving it harder I have heard..... That is the only "downside" I can possibly think of........

James
 
Pretty much it comes down to what you are willing to pay for, and how heavy of a car you are putting a high speed ring and pinion in. For a high speed gears, you will always be in an overdrive, you dont get to pick when to put in in high gear. 3:54 gears are good for heavier cars as long as you have a high comp head to make up for lost torque. 3:27 in my opinion should really only be used in coupes, roadsters, speedster, and maybe a pickup depending on the engine. They are light enough to where the engine wont struggle to bad pulling it. In my opinion (maybe not yours) the transmition/ drive shaft overdrives are the best option. You can run your car up to 50-55 without lugging the engine down then put it in overdrive, where the engine has enough R.P.M's to then pull the o.d. no problem. But if you were to slow down to say 45 you need to take it out of o.d. because then you are lugging the engine causing premature bearing wear because of all the extra pressure. The mitchel is the best o.d. around in my opinion. When we were in colorado, the cars with mitchel's were running 2nd high at 45 mph up the side of mountains leaving the rest of us in the dust. I have a 4 speed synchronized O.D. from Gary Bernard and it works wonderfull and it appears stock. I can get out on the interstate and run 70 mph in the fast lane with the big boys. Hope this was of help, its all up to you and how you want to spend your money. There is no wrong way, when your flipping the bill on all of it.
 
I am running 3:54's in my 30 coupe. They have been in for a couple of years now and work very well. First thing you will notice is that it quiets the car down considerably. Drops rpm for any given speed.
This car is a daily driver between April and December and does a lot ot touring. Has plenty of pep, works just fine.

Steve
 
I don't suppose this will help, but I put 3.54 gears in my roadster, and then installed a Volvo overdrive and a 39 trans. Sure is sweet to drive. I think if I had it to do over again, I'd stay with 3.78 gears, but I'd stay with the OD and 39 trans.
 
. . . I have a 4 speed synchronized O.D. from Gary Bernard and it works wonderfull and it appears stock.

Wow! Every RTS O.D. conversion I've seen has both a tower position half a foot rearward and a different shift lever. How did you move the shift tower forward to the stock position so you could use stock floorboards and a stock mat or rug? I haven't seen this mod for the RTS O.D. ******. Do you have any pictures?
 
I have 3.54:1 in two of my cars. It's a small difference, but noticable and nice. I put a mitchell in Barry's coupe and liked that, and found that except for steep hills, I could just leave it in overdrive. If I could do that with a 26% gear up, then I would think a 13.5% gear up would be fine in this area. In the rocky mountians, not so much. I have a 3.27:1 gear set that I plan to use in my speedster.
 
I put 3:27 gears in my roadster. The car weights 1900# and the engine is at least 100HP. 1939 transmission with zephyr gears. Quite frankly it was not a good choice due to the fact that I was running Firestone dirt track tires that had more grip then I really needed. The rear tire diameter was within 1" of a stock 19" wheel/tire. Went back to a 3:54 that works fine.

I have another A with a T-5 that is a joy to drive. Given the difficulties of installing the T-5, I think that using the Mitchell OD is a wash financially. I just traded a Volvo OD that I had in an old speedster that was easy to use.
 
Wow! Every RTS O.D. conversion I've seen has both a tower position half a foot rearward and a different shift lever. How did you move the shift tower forward to the stock position so you could use stock floorboards and a stock mat or rug? I haven't seen this mod for the RTS O.D. ******. Do you have any pictures?

The shifter is just a stock model a stick. But you have to use a boot over the bottom because part the casting of the tower sticks through the floorboard. It's not big or noticible, it's just where the stick goes into the shifting tower. But as for floor boards and mats, we had to get new ones. The tower is moved back about 4 inches so you have to drill a new hole in the floor board, and cut a new whole in the carpet or you can send a template of the new trans position and lebaron Bonney will cut you a new mat without the first hole in it. People don't even notice it's an aftermarket trans till I tell them.
 
Logan, the "mat" from Lebaron Bonney, is that a carpet mat or a rubber mat. Since my F150 install I've been looking for a "stock" looking rubber mat for my '30 CCPU that doesn't have the shifter and E-brake holes already cut.
 
Logan, the "mat" from Lebaron Bonney, is that a carpet mat or a rubber mat. Since my F150 install I've been looking for a "stock" looking rubber mat for my '30 CCPU that doesn't have the shifter and E-brake holes already cut.

Yes the when i refered to the "mat" i ment carpet or rubber, i just thought that was automatically understood. But as for the stock rubber mat for you pickup, i dont know where you could get one w/o the holes already cut. Like i said you can make a template out of cardboard and send it to Lebaron Bonney or maybe a cheaper company (L.B. is quite expensive but worth the money) and they can cut one out for you that is perfect for you car.
 
A friend put 3.27 gears in a '30 Roadster with stock 19" wheels and tires. He also had a few mods to the engine. It was GREAT! As mentioned you will need a high compression head and would be even better with a new cam (not reground) to maximize your torque curve. With that said, I'm not sure I'd recommend it for most folks. Most "A" owners don't make adequate use of second gear. If you don't regularly shift up and DOWN through the gears then it's not a good choice. If you are the type that habitually coasts around a right turn in third gear THIS IS NOT FOR YOU!
 
2000 had 31 tudor full stock. 2001 put in 3.27 gear, advertised 10-12 mph but you only get 7mph .2003 loaned car to great race x-cup PARIS,tx school. We added 26.6 mitchell, and 5.9 brum. ran withn stock zenith, car performed out of this world. 2003 july I added web carb and that was another great add-on. 2006 had engine inserted by Pete's in Alb.NM. Car runs sooooooo- gooood I always try to get people to drive it. Overdrive at 60 mph rpm is 1810. World meet in dallas I drove 430 miles from my house in Lafayette,LA. ran about 63 mph and took 8 hrs flat getting to motel. that was stopping 3 times for gas and noon meal avg---24.7mpg. When i bought the 3.27 gear it was only 350.00 . BUT you will only get 7 mph. I would get the mitchell and skip the gear because of the price now. But if anyone is comming thru the Lafayette,LA area let me know , you get a free ride.
 
With the 3.27 gear currently out-of-production, your options are limited.

I will tell you that that I prefer the look and driveability of the 3.27 over the Mitchell simply because of the look & the cleaner driving compartment. My experiences are similar to Marco's advice and I find I usually get to educate my customer when they take delivery on how to properly drive their car within their engine's powerband. From then on, they are usually very satisfied as the 3.27 ratio matches their expectations & goals.
 
Iam running a borg warner OD for abot 2 years in my Sport Coupe, stock engine I like it. I have driven a friends car with 3.54 and it seem fine , you find your self down shifting a little more.
 
The shifter is just a stock model a stick. But you have to use a boot over the bottom because part the casting of the tower sticks through the floorboard. It's not big or noticible, it's just where the stick goes into the shifting tower. But as for floor boards and mats, we had to get new ones. The tower is moved back about 4 inches so you have to drill a new hole in the floor board, and cut a new whole in the carpet or you can send a template of the new trans position and lebaron Bonney will cut you a new mat without the first hole in it. People don't even notice it's an aftermarket trans till I tell them.

Exactly my point. It DOES NOT look stock, as you originally stated. I've seen lots of them. Its the first thing I notice when I look at the interior of A's at events. Maybe I'm too picky. I'd like to see an install of a synchro O.D. trans without anything visible in the cabin.
 
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