COMP Cams Hi-Tech Roller Timing Chain SetCast Iron Camshaft Gear and induction hardened billet Steel crank sprocket. Feature 3 keyway crank sprocket for 4 degree incremental adjustability, 4 degree maximum advance retard. Pre stretched, heat treated double Roller chain with heavy duty large pin design Catalog User 1 This Part Fits: Year Make Model Submodel 1977,1980 Buick Century Base 1977 1979 Buick Century Custom 1980 Buick Century Estate 1978 1980 Buick Century Limited 1978 1979 Buick