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Old 11-08-2008, 03:59 PM   #4 (permalink)
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Join Date: Jan 2008
Location: SE USA - East Tennessee
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Josie - '87 Toyota Pickup
90 day: 26.89 mpg (US)

Felicia - '09 Toyota Prius Base
90 day: 51.67 mpg (US)
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Autos are worse than manuals for some simple reasons:

The torque converter at the front of the auto acts as a clutch to let the engine and tranny turn at different speeds, especially when the vehicle is stopped; the torque converter is also a torque multiplier. Electric motors don't need multipliers like that, and when the vehicle is stopped, so's the motor. You do want a clutch for when you're shifting, but otherwise you don't need it much. Also the automatic's shifting system may rely on inputs from engine vacuum, the ECM, or something else that may be lacking or difficult to reproduce from your motor controller. The manual doesn't need any of that, having an infinitely more sophisticated control system: you.

If the auto has a lockup torque converter, that's great, but a lot of folks who build EVs do it with the intent of having a quiet, efficient around-town vehicle. In that operating regime, the lockup never would lock up. So you'd be sending amps into the motor to generate revs that simply disappear in the torque converter's slippage.

I won't say it's a bad plan, but I think you've got a tall order in front of you to convert the 4x4 to a 4x2 wihle also converting it to an EV.

That said, for a homebrew conversion, I wouldn't bother with anything but a truck. There's plenty of room under the hood, lots of loadbearing capacity left in the chassis to carry batteries, etc. But to make life simpler, unless the price is simply too good to pass up, I'd keep shopping for a 4x2 manual.

Hey, buy this one, fix it up cherry and sell it to fund your EV project.

Lead or follow. Either is fine.
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