Cometic C5403-066 MLS Cylinder Head Gasket Bore Chevy Small Block - 4.200 066

The Cometic C5403-066 is a premium Multi-Layer Steel (MLS) cylinder head gasket engineered specifically for Chevrolet Gen-1 Small Block V8 engines with aftermarket cylinder heads. This high-performance gasket features a 4.200-inch bore diameter and a compressed thickness of .066 inches, making it ideal for performance builds requiring precise compression control.

Key Features:

• Multi-Layer Steel (MLS) construction provides superior sealing and durability under high-performance conditions
• 4.200-inch bore diameter accommodates a wide range of small block Chevy builds
• .066-inch compressed gasket thickness allows for precise compression ratio tuning
• Undersized water ports designed specifically for aftermarket cylinder heads, allowing custom port matching and coolant flow optimization
• Engineered for use with aftermarket performance heads on Gen-1 SBC platforms (265, 283, 302, 305, 327, 350, 400)
• MLS technology ensures consistent clamping pressure across the entire sealing surface

Cometic's MLS gaskets feature multiple layers of stainless steel with proprietary coatings that provide excellent resistance to blowout and leakage. The undersized water ports give engine builders the flexibility to machine custom coolant passages to match specific aftermarket head designs, making this gasket an excellent choice for serious performance applications and race engines.