20+ years ago i remember someone on a forum trying to liquid cool the engine in an 1/8 buggy. i can't remember if they modified the head. but i do remember they found copper tubing that was small enough to fit between the fins on the head and wrapped it around. i can't remember what they used for a radiator, but the issue of not being able to run a big enough radiator with enough water quickly became a problem. so people screwing around have tried it.