Quote:
Originally Posted by Don Shillady
Thanks for the commendation, Don, but I am certainly no hero.:o I sort of fell into playing with electric race cars because of my students (long story).
Optima red tops sell for $149 here. I believe the yellow tops are slightly more. I have not researched /used the yellow tops because they are not on the approved list for competition in Electrathon. Electrathon America Electric Vehicle Competition index
Anyway, dealing with electric power has forced me to re-learn some things about horsepower and transmitting power to the driveline. Also, I still have a lot to learn... First, there is little if any need for a multi-speed transmission on these lightweight cars we build and race. The orange car pictured in my previous post has a six-speed derailleur in it, but we never use it. In fact, it has proven to be more problematic than useful. A DC electric motor generates power as soon as you put electricity in the windings. The motor in that car (Briggs Etek) is rated at 3.5 continuous hp at 1725 rpm on 24 volts. However, under load it is capable of 8.5 hp at 24 volts over a wide rpm range. The more load it's under, the more amps it pulls, but hp is there and produced under demand. This is all contrary to internal combustion engines which get their power from combustion /leverage; rpm's = hp up to volumetric efficiency limits.:HMMM:
Maybe a heavier car would require a multi-speed trans to keep the motor operating in its peak efficiency rpm range... As I said, I still have a lot to learn. I will not be converting my coupe or roadster to electric power; I might convert them to run on ethanol when it becomes available in this area. Tenatively, the electric vehicle I envision building for work /grocery getting will be similar to that orange car, but considerably larger. I need it to carry two people and a weeks worth of groceries. If I use a Briggs Etek motor and six batteries, I can wire it for 36 volts. It shold be capable of 40 + mph and have about 40 mile range. The orange car only uses two batteries, according to Electrathon America rules. It will easily top 40 mph, but only for a short time. In a race, which is a 1-hour timed event, it will run a steady 24 to 28 mph for the full hour, depending on the course surface, turns, etc.:)
I don't know if this forum wil be overly receptive to electric vehicles, but I'm sure there are forums just for that. The way things are going, there might be a lot more very soon...