Cometic C5433-040 MLS Cylinder Head Gasket for Chevrolet Big Block Bore - V8 4.570

The Cometic C5433-040 is a premium multi-layer steel (MLS) cylinder head gasket engineered for Chevrolet Mark-IV and GM Gen-V/VI Big Block V8 engines. This high-performance gasket features a .040" compressed thickness and is designed for 4.570" bore applications with aftermarket cylinder heads.

Key Features:

• Multi-layer steel construction for superior sealing and durability under high combustion pressures
• .040" (1.02mm) compressed thickness for precise deck height control
• 4.570" bore diameter accommodates standard and performance big block builds
• Undersized water ports allow custom port matching to optimize coolant flow
• Designed specifically for aftermarket cylinder heads with custom port configurations
• Compatible with Chevrolet Mark-IV, Gen-V, and Gen-VI Big Block V8 engines

Cometic MLS gaskets utilize multiple layers of stainless steel with specialized coatings to provide exceptional combustion sealing while accommodating thermal expansion and engine movement. The undersized water ports give engine builders the flexibility to match-port the gasket to their specific cylinder head design, ensuring optimal coolant circulation and preventing hot spots. Ideal for street performance, racing, and high-output engine builds where precision and reliability are critical.