This a is a Manganese Silicon Bronze Valve Guide Set (8) for a Triumph Spitfire 1962 to 1967 with the 1147 (1200) engine. Why choose a Manganese Silicon Bronze Valve guide? The Bronze has the amazing ability to self lubricate plus the Bronze provides superior heat transfer and resists seizing compared to standard Cast Iron Valve Guides. Rebuild your Cylinder Head once with High Quality Manganese Silicon Bronze Valve Guide.