Cometic C5634-045 MLS Cylinder Head Gasket GM/Mercury Marine Big Block V8 Gen-IV/V/VI

The Cometic C5634-045 is a high-performance Multi-Layer Steel (MLS) cylinder head gasket engineered specifically for GM and Mercury Marine Big Block V8 Gen-IV, Gen-V, and Gen-VI engines. This precision-manufactured gasket features a .045-inch compressed thickness and is designed to accommodate a 4.500-inch bore diameter.

Key Features:

• Multi-Layer Steel (MLS) construction provides superior sealing and durability under extreme pressure and temperature conditions
• Designed for engines with 4 bolts in the lifter valley configuration
• 4.500-inch bore diameter accommodates performance and stock applications
• .045-inch compressed thickness allows for precise compression ratio tuning
• Compatible with GM Big Block Gen-IV, Gen-V, and Gen-VI marine and automotive applications
• Cometic's proprietary MLS technology resists thermal expansion and compression set

Cometic MLS gaskets feature multiple layers of stainless steel with elastomeric coatings that provide exceptional conformability to sealing surfaces. This design ensures reliable sealing in high-performance, high-boost, and marine environments where conventional gaskets may fail. Ideal for both stock rebuilds and performance builds requiring precise head gasket thickness selection.