thanks for all the replies! A couple of the ideas already sound good...The car is a D gas roadster. 292 cubic inch V-8 Chevy. As far as the height of the tank, it is a 14in diameter round tank, 30in long, laid horizontally. The top of the tank will be just above the heads of the engine. How much horsepower does a mechanical water pump take to run? I like the idea of running a remote thermostat. I had not thought about running a loop back , thanks. Off to the shop now!