well this aint on a site, but I got the idea from QFM in another thread....
It's basically kinda having rear suspention...
You can cut the motor well away from the chassis, and have 2 motor wires comming out of the main chassis, to the motor well. Then use a thin piece of plastic to connect the main chassis to the motor well leaving a gap between them (basically mini-z style). This means the rear is using the plastic flexing as the suspention, like the mini-z.
This also means the overall chassis will be longer, so you can use slot car lexan bodies.
Now I know this can be somewhat complicated, but this is just an idea