I share with you an old article on nitro rc micromotor machining.
Years ago I performed these modifications on some of my engines with good results. No racing, just purely amateur use.
I've had a few electric cars in the past...maybe one, but nitro gave me that extra adrenaline rush. I hope to go back to racing with nitro soon, but not having a track and only riding in streets and parks, I must first find a clean enough place on the ground...
unfortunately I have been stopped for several years with this hobby.