Cometic C5640-080 GM/Mercury Marine Gen-IV Big Block MLS Cylinder Head Gasket - V8

The Cometic C5640-080 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 4.580-inch bore diameter and .080-inch compressed thickness, providing superior sealing and durability in demanding marine and automotive applications.

Key Features:

• Multi-Layer Steel (MLS) construction for maximum strength and conformability
• 4.580-inch bore diameter accommodates standard and slightly overbored cylinders
• .080-inch compressed thickness allows for precise compression ratio tuning
• Includes 2 slotted lifter valley bolt holes for proper Gen-IV engine configuration
• Designed for GM and Mercury Marine 1050 Gen-IV Big Block V8 applications
• Superior resistance to blow-out and coolant leakage
• Accommodates thermal expansion and engine movement better than composite gaskets

Cometic MLS gaskets utilize multiple layers of stainless steel with advanced coating technology to create a superior seal under extreme cylinder pressures and temperatures. The .080-inch thickness makes this gasket ideal for performance builds where precise compression ratio control is critical, and the slotted lifter valley bolt configuration ensures proper fitment on Gen-IV block architectures.