RX, I don't think you are able to do that, its already a voltage regulator for servos and ESC. You can maybe do it with the TX. Radio operators of HAM and CB call it peak and tweak. Maybe Illegal to do. Radio systems of RC Futaba and Sanwa are different, each proprietary. One manufacture does better then the other.
FCC compliance come into the picture. Tweaking TX could cause static on home cordless phone that use 2.4mhz which RC runs. Cordless phone are regulated to 120ft from base, and also WiFi wireless on computers. CB limited to 4watts, 2 on walkie talkies. TX and home phones even less.
Be kinda funny when you are messing around on the street, and neighbors phones ringing!!!!