Yellow Titanium Nitride
This thin coating is much harder than the Molybdenum coating (equivalent to 85Rc) and covers the entire valve. The stem, the tip and the valve seat are coated to decrease valve wear on high performance applications. This coating is applied by PVD (physical Vapor Deposition) providing the valve with a very hard, frictionless protective coating. We have tested this coating with many successful engine builders worldwide and found that this coating works very well with the Manganese Bronze valve guides for engines with bucket type tappets where there is no need for a welded or pressed tip, consequently eliminating the risk of breakage.
A silver color coating also applied by PVD (physical Vapor Deposition) and with similar characteristics as the TiN, which works better with factory steel guides.