EV Conversion: Why Keep The Transmission?
by Steve Smith
(Rio Rancho, NM)
Electric Car Motor Installed
Everyone seems to be keeping the transmission in their electric car conversions. I don't get it. If I upscale the motor why can't I lose the transmission and clutch etc? Of course I would need to mount the motor where the tranny is now and get a part milled to connect the drive shaft to the motor.
I'd be inclined to lose the drive shaft too, if I could figure out how to secure the motor to the differential and still let the whole unit rock with the road.
What do you think?
Hi, Steve -
Allen Antonucci here from Duke's Garage.
All great ideas!
For every drive train component to work correctly with your design, you'll want to maintain the stock suspension geometry.
If you attach the motor directly to the stock rear differential it still needs to pivot up and down while being secured to the body somehow like on a hing mount. You may put too much stress on your motor case or over flex your wires because the will need to move up & down constantly with the suspension travel. Best thing for you to do is weld in a VW Beetle rear end, easy to get parts and motor bolts right to the transaxle with a bell housing adapter.
We built a 1965 Mustang with 2 DC motors coupled together "No tranny". Attached by a machined u joint coupler & bearing to the driveshaft. It works great, but the battery packs state of charge is decreased faster and the motor will overheat quicker running at higher RPM's.
If you use a 4 or 5 speed transmission you can reach a higher rate of speed and maintain lower RPM's. That will increase your distance and keep your electric components running cooler.
We have tried lots of ways to accomplish integration of EV parts to a variety of vehicles: 4x4 jeep with a push button shift LEMCO 2spd transmission which was a really tough build...VW Beetles, 356 Beck Speedsters, Ford rangers, GMC Sonoma.
- Allen
Duke's Garage is an electric car conversion company in Westminster, CO specializing in classic car conversions.