Quote:
Originally Posted by Jim Sims
I've considered a project like this; keep the progress reports and images coming. Did you remove any of the transmission internal parts?
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For the transmission I only replaced the 4 seals and the transmission fluid. I'm working on the battery racks and I will post updates. I have more details in my build blog:
Electric Porsche
Quote:
Originally Posted by SteamWolf
Interestig that you have kept the gearbox. Most EV's I've seen were all direct drive.
What is the build cost like? Is it worth the expense to save a couple of grand a year in fuel bills?
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I kept the gearbox because it came with the car and it allows me to use a DC motor. Most direct drive (or fixed gear drive) electrics use AC motors which can spin at higher RPM, with good torque across a wide RMP band. But for torque off the line at 0 rpm, the series wound DC motor is the best. I expect to use 2nd gear up to 45 MPH and 3rd gear at higher speeds. AC motors are expensive for the hobbiest because a lot of the manufacturers only sell to OEM.
A project like this starts at $20,000. I've got a bit more into it because once I got started I couldn't resist getting a bigger battery pack (100 mile range) and a more powerful motor controller. My project is not cost effective because of the high cost of lithium batteries. Payback pencils out to 15 years. I'm buying all my parts at essentially retail price, so a car manufacturer would probably be able to do better. If the battery prices drop, and you could get 300 miles per charge, and refuel in 10 minutes, I feel there would be no technical barrier for electric cars to become viable. I'm doing this project because I love the low end torque of the electric motor, I hate the complexity of gasoline engines, and for 15 years since I first drove an electric vehicle I've wanted one.