Colsibro valve guide set suitable for 5/16″ valves as fitted in TR2-4A & Morgan + 4 engines.
Colsibro is a high-copper alloy with small additions of nickel and silicon, which combine to increase the strength, hardness and wear resistance of the material. The material is vastly superior to phosphor bronze in this application. It is resistant to galling or nipping up in arduous working conditions.
