Cometic C5639-045 GM Mercury Marine Gen-IV Big Block V8 Cylinder Head Gasket .045" MLS 4.530" Bore

The Cometic C5639-045 is a premium Multi-Layer Steel (MLS) cylinder head gasket engineered specifically for GM and Mercury Marine Gen-IV 1050 big block V8 engines. This high-performance gasket features a .045-inch compressed thickness and is designed to accommodate a 4.530-inch bore diameter, providing exceptional sealing capabilities for demanding marine and automotive applications.

Key Features:

• Multi-Layer Steel (MLS) construction for superior durability and heat resistance
• .045-inch compressed gasket thickness for precise compression control
• 4.530-inch bore diameter compatible with Gen-IV big block specifications
• Includes provisions for 2 slotted lifter valley bolts for proper engine assembly
• Designed specifically for GM/Mercury Marine 1050 Gen-IV big block V8 engines
• Advanced MLS technology provides excellent rebound characteristics and conformability

Cometic's MLS gaskets are built with multiple layers of stainless steel, providing superior torque retention and resistance to extreme cylinder pressures and temperatures. The embossed design ensures optimal sealing around combustion chambers, coolant passages, and oil galleries. This gasket is ideal for both stock rebuilds and high-performance marine engine applications where reliability is critical.