Over 16 years of Over-the-Road testing by thousands of EVO and Twin Cam Engines with valve lifts of up to .750 lift has resulted in NOT ONE SINGLE REPORTED FAILURE OR LOSS OF SEAT PRESSURE WITH ANY KNIGHT PROWLER VALVE SPRING!
WE DON’T COPY AND WE DON’T IMITATE!
Every spring that is manufactured for our KNIGHT PROWLER Cams comes from PSI with wire that is made from the highest quality Chrome-Silicone alloys. The hard to find rod material for these alloys is 100% Kobe steel, long considered necessary to manufacture the cleanest, purest valve spring available in the world. KNIGHT PROWLER Valve Springs have an optional, proprietary, multi-step, surface enhancement process that has been proven to increase a spring’s endurance limit. This process can be applied to any level of the KNIGHT PROWLER series of springs. It is a very beneficial process for those looking for an increase in endurance while maintaining their existing setup.