Cometic C5639-070 GM Mercury Marine Gen-IV Big Block MLS Cylinder Head Gasket - V8

The Cometic C5639-070 is a high-performance Multi-Layer Steel (MLS) cylinder head gasket engineered specifically for GM and Mercury Marine 1050 Gen-IV Big Block V8 engines. This precision gasket features a .070" (1.78mm) compressed thickness and a 4.530" bore diameter to provide optimal sealing in demanding marine and high-performance applications.

Key Features:

• Multi-Layer Steel (MLS) construction for superior sealing and durability
• .070" compressed gasket thickness for precise compression ratio tuning
• 4.530" bore diameter designed for Gen-IV Big Block V8 engines
• Includes 2 slotted lifter valley bolt holes for proper installation
• Engineered for GM and Mercury Marine 1050 Gen-IV applications
• High-temperature resistant materials withstand extreme combustion pressures

Cometic's MLS technology utilizes multiple layers of stainless steel with specialized coatings to create a gasket that recovers from thermal expansion and contraction cycles. This design makes it ideal for marine engines that experience frequent temperature variations and high-performance builds requiring precision head sealing. The gasket's construction allows for proper clamping force distribution across the entire sealing surface, preventing blown head gaskets even under demanding conditions.