> http://www.teslamotors.com/performance/acceleration_and_torque.php
>
> Gets by with only two gears, and can supposedly be kept in second gear at 
> all times while still performing adequately.

I have just been playing about with the details from that car in a simulator 
I have here.  Some interesting facts:

1) The motor output torque seems to be limited to exactly the right amount 
at low rpm to provide roughly 1.1g of acceleration in 1st gear.  This is 
probably matched to the tyres on dry tarmac to provide optimal acceleration 
without having to worry about traction control.

2) It really would benefit from having a 3rd gear.  It runs out of steam at 
125mph, but that's not because the air drag equals the engine power, but 
because it's run out of rpm in 2nd gear.  If I give it a 3rd gear with a 
gear ratio of 1.15 it can get up to 145 mph which is a bit more impressive 
for a car with really good low speed performance.  In theory that's the true 
top speed possible with this electric motor and that body shape.

3) I made it have a race with a stock BMW 123d (I just happened to have all 
the details for that car) and it's quite interesting.  Obviously the insane 
low speed torque helps the electric car to get a really good lead from a 
standing start, but after just 7 seconds the BMW is now accelerating faster. 
However it takes until 48 seconds for the BMW to catch up because it's so 
much slower at the start.  After that the BMW just pulls away due to it's 
better high-speed performance, moving roughly 10 metres further away every 
second.

In conclusion, you'll be the quickest on the road under 40 or 50 mph, and 
one of the quickest up to 80 or 90 mph.  Around 100 and above "normal" cars 
will be passing you... :-)

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