Borg Warner DG
- Thread starter DaveHerns
- Start date
Yes, they had a direct drive clutch in the converter itself, so effectively a lockup converter. Some also had intermediate gear speedhold. I don't know a lot about them other than they have cast iron casings so they're bl**dy heavy. I've done a few bits and pieces on them, with a high success rate, but that's only because I refuse to get too involved with them. If I got more involved that success rate would take a bit of a dive I reckon....
To keep up the Rover content, they were fitted to all the P5's apart from the Mk111.
To keep up the Rover content, they were fitted to all the P5's apart from the Mk111.
The Rovering Member
Well-Known Member
My Mk1a 3 litre had the speed hold DG box. And using the hold on second gear became second nature to me.
Umm, very interesting topic Harvey!
I found some enlightening info on the B-W DG:
Borg Warner - Detroit Gear 250 Transmission -
The Studebaker Automatic Drive transmission was - and is - one very fine
transmission. Popular Science did a very nice piece on the Automatic Drive
in 1950.
Automatic Drive was a joint effort of Studebaker and Borg-Warner (Detroit
Gear Division). The transmission allows the driver to switch from torque
converter-gear drive to direct drive and back again at any speed between 18
mph and 58 mph. Above 58, the torque converter is always locked out, below
18 it is always locked in.
Popular Science gave this summary of what a driver can do with Automatic
Drive:
"One criticism often voiced against automatic transmissions is that they
deprive the driver of choice. That this isn't true of the Studebaker/Borg-
Warner drive is shown by the following description of what happens when the
selector lever is in the drive position. It's also eloquent proof that
motorists must understand their transmissions to get the most out of them.
"At the moment of starting, with the selector lever at "D," the power
train is through the torque converter and intermediate gear. Starting
torque ratio in the transmission (not counting the advantage of rear-axle
ratio) is 3.08 to 1, or more than three turns of the engine crankshaft for
every turn of the propeller shaft. Automatic shifts from intermediate gear
to direct drive occur within the following limits, depending on speed,
throttle position and load:
"1. Starting with a very light accelerator depression, the transmission
shifts from intermediate to direct at about 18 mph.
"2. Starting with full throttle (not depressed past the kick-down abutment
on the floor-board), the transmission shifts into direct at about 35
mph.
"3. Staring with any accelerator depression between between light and full
throttle, the transmission shifts into direct between 18 and 35 mph, depending
on accelerator position.
"4. Starting with full throttle and accelerator depressed past the kick-
down point, the shift into direct drive occurs at about 58 mph.
"5. Coasting in direct with accelerator released, the transmission downshifts
into intermediate gear plus converter at 12 mph.
6. Direct drive may be over-ruled to provide added torque available in
intermediate by depressing the throttle to the kick-down point at any
speed below 50 mph."
P.S. Sorry if I've spilt the beans. I thought you all would've Googled by now :idea:
I found some enlightening info on the B-W DG:
Borg Warner - Detroit Gear 250 Transmission -
The Studebaker Automatic Drive transmission was - and is - one very fine
transmission. Popular Science did a very nice piece on the Automatic Drive
in 1950.
Automatic Drive was a joint effort of Studebaker and Borg-Warner (Detroit
Gear Division). The transmission allows the driver to switch from torque
converter-gear drive to direct drive and back again at any speed between 18
mph and 58 mph. Above 58, the torque converter is always locked out, below
18 it is always locked in.
Popular Science gave this summary of what a driver can do with Automatic
Drive:
"One criticism often voiced against automatic transmissions is that they
deprive the driver of choice. That this isn't true of the Studebaker/Borg-
Warner drive is shown by the following description of what happens when the
selector lever is in the drive position. It's also eloquent proof that
motorists must understand their transmissions to get the most out of them.
"At the moment of starting, with the selector lever at "D," the power
train is through the torque converter and intermediate gear. Starting
torque ratio in the transmission (not counting the advantage of rear-axle
ratio) is 3.08 to 1, or more than three turns of the engine crankshaft for
every turn of the propeller shaft. Automatic shifts from intermediate gear
to direct drive occur within the following limits, depending on speed,
throttle position and load:
"1. Starting with a very light accelerator depression, the transmission
shifts from intermediate to direct at about 18 mph.
"2. Starting with full throttle (not depressed past the kick-down abutment
on the floor-board), the transmission shifts into direct at about 35
mph.
"3. Staring with any accelerator depression between between light and full
throttle, the transmission shifts into direct between 18 and 35 mph, depending
on accelerator position.
"4. Starting with full throttle and accelerator depressed past the kick-
down point, the shift into direct drive occurs at about 58 mph.
"5. Coasting in direct with accelerator released, the transmission downshifts
into intermediate gear plus converter at 12 mph.
6. Direct drive may be over-ruled to provide added torque available in
intermediate by depressing the throttle to the kick-down point at any
speed below 50 mph."
P.S. Sorry if I've spilt the beans. I thought you all would've Googled by now :idea: