Well after much hard work and experimentation I have successfully mosfet modded a ZipZap SE to have a significant increase in speed and torque as well.
The stock ZZ SE with a red 21.5 motor and blue (12:1) gears trundles along at a pitiful 4.5km/h (about 3mph) which is a real yawn.
I delved in the the driving/switching circuits and came up with a way to triple the driving speed of the car, increase the torque and keep all the proportionality of the control, both in speed and steering.
It now loves the high speed motors and the tall gears.
If you put in a purple 3.4 'turbo' motor, and the red gears (8.25:1) it will now scream along at around 13 km/h (around 8.5 mph) with full speed control in a smooth range from 5 to 13 km/h (3 to 8.5 mph).
It takes the best corners, with the propo control it will turn wide or sharp, but all the time you are in total control.
It is kinda strange to have such good control of these tiny cars at these speeds, but hey I'm not complaining.
I am once again offering to do these mode for people to their cars. In short, you send me your car, I mod it, test it, and send it straight back to you. All the info is on my website, including prices etc, (have a good look around), then email me and we can get things happening from there.
uA