Valve Seat Material Selection for High-RPM Tuned Engines with Aluminum Cylinder Heads

For valve seat applications in high-RPM tuned engines, AMPCOLOY® 83 is the standard recommendation due to its higher hardness, which is the primary requirement for valve seat performance. Where higher thermal conductivity is a priority, AMPCOLOY® 95 is an alternative, but it will need to be replaced more frequently due to its lower wear resistance.

When an aluminum cylinder head is used, the cathodic-anodic effect between the aluminum and the copper alloy should be considered. The aluminum head will be more susceptible to corrosion in this pairing, which may require more frequent engine overhauls. Despite this consideration, AMPCOLOY® alloys are often the only viable solution for removing heat in sufficient quantities from the valve seat area.