Cometic Chevrolet 348/409 W-Series Big Block V8 .045in MLS Cylinder Head Gasket - 4.375in Bore

Starting with a compressed thickness of 0.036 inches, this Cometic Multi-Layer Steel (MLS) head gasket is built for serious performance in Chevrolet 348/409 W-Series Big Block V8 engines. It features a 4.375-inch bore and a specific 0.045-inch thickness, designed to handle the demands of high-output applications. This gasket is a solid option for a wide range of classic Chevrolet vehicles, including models like the Impala, Bel Air, and C10 Pickup from the late 1950s and early 1960s.

The construction uses multiple layers of stainless steel, which not only adds strength but also allows the gasket to rebound and resist corrosion. The outer layers are coated on both sides with Viton, a heat-resistant rubber material capable of withstanding temperatures up to 482 degrees Fahrenheit. This advanced coating is designed to perform reliably in harsh sealing environments and on various surface finishes, making it suitable for combinations of aluminum heads with aluminum or cast iron blocks. The center shim layer is also stainless steel, allowing for precise thickness control.

Because it's an MLS gasket, it doesn't require any additional sealants, simplifying the installation process. This makes it a popular choice for engine rebuilds where sealing performance is critical.