How do you cool you motor in between passes?

Don't laugh I am telling my age but I have watched the "Little Red Wagon" back in the day return to the Pits after a pass and they literally had a brass fitting fitted to each cylinder head which one opened up like a petcock and dumped hot water (he only ran water at that time thru the engine) on the ground in the pits and hooked a garden hose to the other and pumped fresh cool water thru it as it was running to cool it off. I don't think the Pit officials will let you do that any more got to keep mother earth green nowdays and they might be afraid you would spill coolant not water on the ground.