Fits 5.7L and 6.1L Hemi LX's Reduced engine temperatures add life to your engine and provide a denser air/fuel mixture which helps produce more horsepower. Consistent control of engine temperature allows an engine to operate at its peak efficiency no matter what the driving conditions. The factory 195 degree thermostat simply cycles open and closed, this reduces cooling efficiency in any engine. With the JET 180 degree thermostat you get consistent engine cooling and a precise metering of water throughout the engine. Constructed of stainless steel the JET Thermostat offers a lifetime warranty.