Extensive R&D on all applications to provide high performance components that last longer than OEMBlack Diamond valves are one-piece forgings made from 21-4N high-performance stainless steelTrademarked Black Diamond treatment provides a stem that has a longer life capacityAll valve guides are made of Ampco-45, a high-performance nickel-bronze material that provides excellent thermal and wear propertiesSuper-clean silicon wire used in valve springs is ground, not shaved, and X-rayed at regular intervals to check for flawsTitanium retainers are made from 6AL4V titanium alloy; designed to be the strongest and lightest for ultimate performanceKeepers not included; use OEM keepers and bases, as notedValves and guides are sold each; spring kits come complete for one motor and include instructionsAll components made in the U.S.A.
