The latest generation FORD-4D thermostat has been upgraded with modern features like a rubberized diaphragm and a larger heat motor. It's a direct-fit unit with proper coolant bypass control, so you're guaranteed maximum efficiency from your cooling system. All components are manufactured by an OEM supplier making this the very best available for your application.

This thermostat will provide the best possible heat dissipation from your setup and even deliver better overall performance than our competitor's 160° thermostats. Reische believes the 170° opening temp is the ideal balance for high performance engines, providing high flow to your radiator by mid-180 temps while still providing good all season performance. With proper fan settings your coolant temps in cool weather will be in the 170s and in hot weather the 180s, giving those running high levels of timing and/or boost added protection against engine-damaging detonation, as well as, maximum hp.