Cometic Chevy Mark-IV GM Gen-V/VI BB 4.630in Bore .120in MLS Head Gasket

If you're working on a Chevrolet Mark-IV, GM Gen-V/VI Big Block V8, this Cometic Multi-Layer Steel (MLS) head gasket is built to handle serious power. It's designed with a 4.630-inch bore and a compressed thickness of 0.120 inches, making it a solid choice for high-output engines where sealing is critical. This gasket fits a wide range of vehicles, including classic models like the 1965-1975 Chevrolet Bel Air, 1965-1972 Chevrolet Impala, and 1967-1972 Chevrolet Camaro.

Cometic's MLS gaskets are well-built using multiple layers of stainless steel. The outer layers are coated with Viton, a heat-resistant rubber material that can handle temperatures up to 482°F (250°C) and works well with different block and head materials, like aluminum heads on cast iron blocks. The stainless steel layers provide increased strength and resist corrosion, while the center shim layer can be varied to achieve different thicknesses. These gaskets are designed to provide maximum sealing performance without needing additional sealants, and they are suitable for aftermarket heads, featuring undersized water ports that allow for customization.