DescriptionWe choose to use the copper based C63000 nickel-aluminum bronze as a material to make our bronze valve guides because of its ideal characteristics for the application. The 5% nickel content provides superior resistance to wear, and the approximately 80 percent copper content delivers outstanding heat conductivity. KPMI® guide profiles are designed to have minimal effect on the airstream while maintaining critical cross sectional thickness in high temperature areas, which promotes high performance and endurance.QuantityPkg. of 1MaterialC630 BronzeTypeIntake / ExhaustOutside Dia.: (G)0.3774″ / Std.A0.435″B0.495″C0.730″D1.020″E0.475″F0.2154″