Two thoughts...
1. Build a custom 4-cell pack (2/3rds the power of the standard 6), all the electronics should still work as usual.
2. Since you are using a stick transmitter, one trick I have seen before is to put a small self-tapping screw in front of the throttle stick, and adjust it as a travel limiter. Although I know someone else that did something similar for their grandson, and their grandson soon realised that pushing the trim forward made the car faster again!
|