Cometic Pontiac 326/389/421 V8 .070in MLS Cylinder Head Gasket - 4.300in BoreThe HP shim technology increases clampload around the combustion chamber, thereby increasing the sealability of the head gasket around the open deck block. This Part Fits: Year Make Model Submodel 1959 1966 Pontiac Bonneville Base 1959 1962 Pontiac Bonneville Custom 1959 1966 Pontiac Bonneville Safari 1964 1966 Pontiac Catalina 2+2 1959 1966 Pontiac Catalina Base 1959 1966 Pontiac Catalina Safari 1962 1966 Pontiac Catalina Ventura 1962 1966 Pontiac