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marcexec

Here is an article I have written about using automatic transmissions in an EV.

http://mysite.verizon.net/davidharri...EV/Auto_EV.pdf

An interesting discussion on the topic:

http://www.diyelectriccar.com/forums...evs-29101.html

infantry11b · #2 02-24-2010, 12:08 AM

thanks for the information.
if you have to keep your engine running at 700 rmp you are using juice sitting still - when your motor should be resting?
if your engine will rev at 4k why use a trans at all? dont you have max power and torque from the get go? cant you just use a motor with 300 or 400 hundred ft lbs of torque and hook it right into the rear end?
most of my v8's run at about 1600 rpm at 65 or 70 - if your motor wants to run at 4k then you can even make it faster off the line with 4:11 gears and still do 70 without over running the motor.
or is that too simple because i am forgetting something.

justanothernoob · #3 05-21-2010, 08:28 PM

I think the issue you miss is that most cars built in the last 3 decades are fwd and to top that off they are about 70% automatics to boot. So no 3rd member/axle assembly to just bolt 'er up to! Plus then ya gotta put an electrical reverse in it- not that tough I would think. So I think the issue he is trying to work around is admirable, however maybe slightly out of focus. Really dont need the idle circuit really- just have the controller come up to 700 rpm rather quickly, get the car moving a bit, lock up the convertor as soon as possible and go from there. Most newish transmissions will have some sort of lock up feature and it should be locked on as soon as you reach a road speed matches that preselected motor speed to allow full power from the motor to the wheels without slippage in the torque convertor. It does beg a point that I am going to research... Is it possible to remove the transmission section from the axle section of any newer vehicles transaxles? Seems the easy way to go in my limited thought processes. Just bolt the motor to the old output shaft and wham there ya go. Or am I missing something???