Cometic Chevy BB 4.375in Bore .040 inch MLS 396/402/427/454 Head Gasket

Starting with a compressed operating thickness of 0.040 inches, this Cometic Multi-Layer Steel (MLS) head gasket is built for serious sealing. It's designed for GM Gen-V and VI Big Block V8 engines with a 4.375-inch bore, making it a solid choice for those rebuilding or upgrading these powerful V8s, found in trucks like the Chevrolet C1500 or GMC C2500 Suburban from the early to mid-90s.

The construction uses multiple layers of stainless steel for increased strength and resistance to corrosion, which also allows the gasket to rebound effectively. The outer layers are coated on both sides with Viton, a heat-resistant rubber material capable of handling temperatures up to 482°F (250°C). This advanced coating is crucial for sealing in harsh environments and works well with both aluminum and cast iron blocks, preventing issues caused by the shearing forces between different metals. The center layer is also stainless steel and can be varied to achieve different thicknesses, ensuring a precise fit for your specific engine build.

Because these MLS gaskets are well-built and designed for high-output engines, they don't require any additional sealants, simplifying installation. This makes them a popular option for engine builds where maximum sealing performance is a priority.