Cometic C5403-080 MLS Head Gasket Chevy Small Block Bore Thick - 4.200 080

The Cometic C5403-080 is a multi-layer steel (MLS) cylinder head gasket engineered specifically for Chevrolet Generation I small block V8 engines. This precision-manufactured gasket features a 4.200-inch bore diameter and .080-inch compressed thickness, making it ideal for high-performance and racing applications where precise compression control is critical.

Key Features:

• Multi-layer steel construction provides superior sealing and durability under extreme pressures and temperatures
• 4.200-inch bore diameter accommodates both standard and slightly over-bored small block Chevy engines
• .080-inch compressed thickness allows for fine-tuning compression ratios in performance builds
• Undersized water ports designed for aftermarket cylinder heads, allowing custom port matching and coolant flow optimization
• Eliminates the need for retorquing after initial installation, unlike traditional composite gaskets
• Compatible with aluminum and iron cylinder heads when properly prepared

This gasket is designed for use with aftermarket performance cylinder heads on Gen-1 small block Chevrolet engines (262-400 cubic inch). The undersized water ports give engine builders the flexibility to custom-match coolant passages to specific head castings for optimal flow and sealing. MLS gaskets require smooth surface finishes (typically 50 RA or better) for proper sealing.