Cometic BB 4.630in Bore .060 inch MLS-5 396/402/427/454 Head Gasket

If you're rebuilding the top end of a Chevrolet Mark IV Big Block V8, getting the head gasket right is crucial for sealing combustion pressure. This Cometic MLS-5 head gasket is built for those high-output engines, offering a compressed thickness of 0.060 inches and a bore size of 4.630 inches, designed to fit a range of popular V8s like the 396, 402, 427, and 454 cubic inch displacements.

Cometic uses a multi-layer steel (MLS) construction for these gaskets, which gives them increased strength and the ability to rebound, helping them resist corrosion and withstand the forces between aluminum heads and cast iron blocks. The outer layers are coated with Viton, a heat-resistant rubber material that can handle tough sealing environments and surface finishes, meaning you don't need to add any extra sealants during installation. The center layer is stainless steel, and its thickness can be varied to meet different requirements, which is how they achieve this specific 0.060-inch compressed operating thickness.

This gasket is a solid option for many Chevrolet applications from the mid-60s through the early 80s, including models like the Impala, Chevelle, and Corvette, ensuring a strong seal for your rebuild.