MTNTK Performance is excited to announce the next generation of engine cooling available for all ’08-’17 Polaris 800 CFI Engines. The MTNTK Cool Head offers a simple and effective way to efficiently cool your engine and lower the thermostat operating temperature without any permanent modification to the engine. Simple bolt-on performance makes the MTNTK Performance Cool Head easy to install and easy to use. The increased size and overall volume of the thermostat, thermostat housing and billet head shell allows for more coolant to flow easily throughout your engine with less restriction. The MTNTK Performance Cheater Head Shell and Superior Dome Design delivers maximum detonation suppression, better throttle response and more horsepower. PLUS, the MTNTK Performance Cool Head Kit does not require any type of fuel controller. Add the MTNTK Performance Tunnel Cooler for the Ultimate Engine Cooling System!