Ford Midget engine Owners Manual 2006

The Focus Midget engine is equipped with an opposite rotation water pump impeller, and the water pump pulley turns in the opposite direction when compared to the street version of the engine. This does not reverse the coolant flow through the engine, it simply allows the pulley to be driven with the HTD belt instead of using the back-side of a serpentine belt. No modifications to the water pump impeller or water pump pulley are allowed.

Coolant exits the head at the cast elbow located at the rear of the engine, and enters the engine at the pump. Since the engine runs on methanol, and the compression ratio has not been raised, excessive heat is generally not a problem. Therefore, a standard Midget-type radiator has proven more than adequate. High pressure, racing radiator caps have not been needed to maintain acceptable temperatures, 16 lb. caps have been adequate. All main coolant lines should be at least –10, or 5/8” inside diameter.

http://www.focusmidgets.com/Specs%20Rules_files/OWNERS_MANUAL_2006.pdf