[GTX_SlotCar]

Originally Posted by major

....Thought you were a little off topic, diy electric car you know. But your toy is an electric vehicle. You going to take what you learn with that and do an electric car?...

Major, thanks for your very useful information. I am off topic with my vehicle. Hopefully the answers you provided will also be useful to some here, and helpful for their projects. Sometimes when one industry needs answers, the best place to get it is from the experts of another industry.

I have given some thought to making an electric car. I'd have a lot to learn. In my case, my office is about 6 miles from home. Mostly 40mph speed limit, and I take one daily trip to the post office - another 4 miles. 16 miles daily at very inefficient gas mileage. Here in Maine, I could use a simple electric car - even without heat - for 6 or 7 months (the regular motorcycle season). I would think that a fairly simple electric vehicle, not to be driven in snowstorms or when the windshield might freeze, might be something I could build. 25 to 35 miles per charge is all I'd need. You know, it's not that I can't afford the gas, but it bothers me that there's nothing available that's optimized for this kind of driving. And, a lot of people I know drive the same way I do.
Anyway, thanks for your help.

Gary

[GerhardRP]

I played with some performance curves for an xp1227a motor [a souped up ADC 8", I think]. I got a family of curves from kta-ev. The most interesting plot is efficiency vs. power [in watts on the graph]. The parabolas are for various applied voltages, while the falling lines are for various RPM, 1 kRPM at the bottom and 6 kRPM at the top. The lesson is to keep the RPM's HIGH. Note that the data are a little ragged at low torque and high RPM. The second graph is power vs. torque.
I've tried to attach the graphs, I hope it worked.

[roflwaffle]

Those graphs are exactly (Well, except for not having data under 1k rpm or efficiency data at really low power levels ) what I was looking for, and they seem to square pretty well with what major mentioned, thanks Gerhard!

[GerhardRP]

I'll edit the graphs later for the low RPM data later. As for low power, I would like to see that also, but I've never seen any. My modeling could use a family of Stalled torque numbers, also including low current... no fancy dyno needed.