[Sneeck]

No, the lower the turn's the faster the motor goes. Only like Squee explained, with a 5 or 6 turn motor on 20 cell's the rpm will be way to high to gear it down and not blow a motor or controller. So the solution is to find a higher wind motor which has no problem to gear it for speed. You use the motor's torque to do that, not the rpm.

Onto the car, that center shaft will go. It's alum, it won't last long with the weight of 20 cell's. But how on earth can we judge the strength of this car by looking at some picture's?