Cometic C5640-066 GM Mercury Marine Gen-IV Big Block MLS Cylinder Head Gasket - V8

The Cometic C5640-066 is a high-performance multi-layer steel (MLS) cylinder head gasket engineered specifically for GM/Mercury Marine 1050 Gen-IV Big Block V8 engines. This precision-manufactured gasket provides superior sealing and durability in demanding marine and high-performance applications.

Key Specifications:

• Multi-Layer Steel (MLS) construction for maximum strength and heat resistance
• 0.066-inch (66 thousandths) compressed thickness
• 4.580-inch bore diameter for proper cylinder sealing
• Includes two slotted lifter valley bolt holes for secure installation
• Designed for GM/Mercury Marine Gen-IV Big Block V8 1050 engines

Cometic's MLS gaskets feature multiple layers of stainless steel with an advanced coating system that provides exceptional conformability to sealing surfaces. The embossed layers create a superior seal around combustion chambers, water passages, and oil galleries while maintaining consistent clamping force across the entire gasket surface. This design makes the C5640-066 ideal for marine applications where resistance to vibration, thermal cycling, and corrosive environments is critical.