[Piwoslaw]

Originally Posted by aspera

Land speed racecars also use ballast tanks instead of radiators. Those tanks contain cold coolant. After the end of the run the tanks are hot and are allowed to cool down. The ballast tanks allow the cars to seal up the front grille entirely. Running without a radiator wouldn't work on a street car, but adding a ballast tank *IN ADDITION TO* a radiator would create a buffer so the car wouldn't overheat AS QUICKLY. That might help some of you guys that only have a postage stamp sized hole in your air dams.

Having a balast tank would also slow down the inefficient warm-up stage of the engine. A good idea would be to have large tank of coolant which would be closed at lower temperatures. Only a small amount of coolant would be left in the engine/radiator loop. Once the engine warms up to optimal temperature, the tank would slowly open, letting its cooler contents gradually mix with the warmer coolant in the system. When the car parks and the engine is turned off, the extra amount of coolant in the tank acts as thermal mass, so when the car starts again later it has lost less heat. Also, a slower rate of heating/cooling is better for the engine parts.