OVERSIZED VALVES - The oversized head diameter is designed specifically for each application, significantly improving the flow rate. ? WAISTED STEM - The waisted stem allows a greater volume of air/gases to enter and exit the combustion chamber as the valve extends. (not available on some models) ? ENGINE SPECIFIC DESIGN - Each valve is designed and precision machined specifically for the intended engine/application.The head, face, stem and lock groove designs have also been optimized to enhance sealing performance, efficiency and durability.
