I've been running model boats on 2.4 radios for years without issues from the engine's ignition system. They use resistor plugs but otherwise have standard industrial magneto ignitions. Gasoline model airplane flyers also run ignition engines without issues. What do you use for plugs? What radio system do you use? It's possible that low cost radios wouldn't have the frequency shifting systems that nearly all high quality radios use these days.
Lohring Miller