Overdrive or not???

29RPU said:
Ok, rookie question, but the above Volvo...This is essentially like the Mitchell correct, looks to be in the driveline. So where does one get the Volvo version? Is there fabrication to create this? What is the volvo deal? Thanks.
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You are correct the Volvo and BorgWarner are fabrication pieces. When looking at these you have to have faith in the person doing the fabrication that the alignment is correct in the torque tube and the welds are good. We did an article in the Model A Times Summer 2005 where we compared the three available overdrives and listed vendors who did the fabrication. We installed all three units in cars and tested them out.
 
the "volvo" is a Laycock De Normanville OD, which was in Volvos, MG's Jaguars, Austin Healeys and other European cars. Parts are still available. They shift with the flick of a switch, Downshifting from 3rd to 2nd over on a hill is a breeze...you flick the switch while you are double clutching and its a smooth as silk, unlike the clunky BW. The guy I got mine from is Rich Little in Shafter, a small farm town near Bakersfield Ca. Last I knew his email is: mrovrdrv@earthlink.net
 
Got a question about overdrives. About them I'm dumber than a rock. Driving say 50 MPH in hilly country in overdrive wouldn't that be lugging the engine up the hilld? and if you have to shift to a lower gear whats the advantage ? Does the unit have freewheeling ??? If so , kinda hard on the brakes ? As I said I need learnin. Tony
 
Tony S said:
Got a question about overdrives. About them I'm dumber than a rock. Driving say 50 MPH in hilly country in overdrive wouldn't that be lugging the engine up the hilld? and if you have to shift to a lower gear whats the advantage ? Does the unit have freewheeling ??? If so , kinda hard on the brakes ? As I said I need learnin. Tony
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Tony,
Overdrives are just like having another, higher gear. Like all of your other gear ratios, there's a speed and load range where they are helpful and other conditions where they can be harmful. Unless you have a really souped up motor with pressurized oil to bearings, you will need to downshift when pulling any but the slightest hill at 50 mph. Where you get your money's worth is on level ground at cruising speed--sounds like Florida to me. Then you can get the same speed with fewer motor rpms and less engine wear (UNLESS motor is being lugged), better mileage (maybe only slightly), and quieter ride.

None of current options are free-wheeling, unless you want to throw it into neutral--which I believe is illegal.

Steve
 
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In regards to peak HP being 40. I thought this was at 2200rpm on the A engine. If your going 60 you've already passed the peak and your power is dropping off big time. I would think overdrive would allow you to drop your RPM's right back into the power band and run 60-65mph with ease.

Perhaps i'm wrong about where the power peaks?
 
the borg warner will free wheel, but I strongly recommend against a BW overdrive.. they're cumbersome to operate, parts are difficult to impossible to find, and they have a troublesome reputation with some owners. BWs are cheaper though, for reasons having to do with low demand due to their problems. A Volvo set up is about 1/2 the cost of a Mitchell, but the wait list is long, and a Mitchell can be delivered when its ordered. I use my OD most often in 2nd gear when climbing hills. Its the perfect in between gear. Its 26 %, which means when I am driving at 60 in high on the freeway, the engine is turning at the equivalent RPM as 48 in direct, which happens to be the sweet spot in my engine. I take it out of OD at 45 MPH on flats or at 50 on hills to avoid lugging. John LaVoy is very correct to suggest you make sure the machinist who does the conversion on Volvos or BWs knows what hes doing. With a Mitchell, you will have none of those concerns.
 
Pat,Who is selling the converted Volvo unit for half the price of the Mitchell? I can lay my hands on plenty of the Volvo units still in the Volvos,although you have to sometimes take two or three apart to get enough for a good one.For some reason where I am the Volvo units are pretty well used up by the time they reach the junkyards.Most seem to have 3-400,000miles on them.Real popular commuter car here.
 
29RPU, Rich Little in Bakersfield, CA makes a Volvo overdrive conversion. The last time I talked with him there was about a 12 month waiting list. This may be shorter now. His phone number is: 661-746-2651. I have one of his units and really love it. Wayne
 
I have a BW in my 31 p/u and a Vovlo in my 31 slant T/S. Without a doubt the Volvo is easier to use. Have used it for 5-6 years. Works Great.
Both cars have Brumfield 5.9 heads.
They cruise great at 55-60 all day.
I would never take a model A on a long tour (100 miles+) without an O/D.
My Volvo was built by Rich Little in Bakersfield - best in the business.
The guy in Southern CA had problems with his welds!
 
Keith True said:
Pat,Who is selling the converted Volvo unit for half the price of the Mitchell? I can lay my hands on plenty of the Volvo units still in the Volvos,although you have to sometimes take two or three apart to get enough for a good one.For some reason where I am the Volvo units are pretty well used up by the time they reach the junkyards.Most seem to have 3-400,000miles on them.Real popular commuter car here.
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I got mine from Rich Little some time ago. It was 1200 when Mitchells were 2200. Rich re-builds them completely, offers an optional oil resevoir and makes a beautiful conversion. He is backlogged quite a bit, typical for good machinists, and he is retired so does not put in a full day either. I have a BW, a Mitchell and the Volvo, which is my favorite for ease of use and low profile appearance. The Mitchell is a good OD, but I do not like the extra shift lever. I have the Volvo switch on the lever for shifting on the fly when double clutching, but you can hide it under the floor mat using an old foot operated dimmer switch, and no one will know the car is not stock....Unless they look under the chassis.
 
The so called Volvo overdrive was actually made by a British company. The overdrives were used in Jaguar, Triumph, etc. but are most easily found in Volvos from the 70's and 80's. Some serious machine work is required to install them in a Model A driveline. Usual cost for one ready to install is $1000-1200. The overdrive is electric/hydraulic, shifts like an auto trans, and requires only a switch to operate. There have been guys in Texas and Calif. building them in the past. Not sure of availability today.
 
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