Cometic C5640-040 GM Mercury Marine Gen-IV MLS Cylinder Head Gasket Bore - 4.580 040

The Cometic C5640-040 is a premium Multi-Layer Steel (MLS) cylinder head gasket designed specifically for GM/Mercury Marine 1050 Gen-IV big block V8 engines. This .040" thick gasket features a 4.580" bore diameter and is engineered to provide superior sealing performance in high-performance marine and automotive applications.

Key Features:

• Multi-Layer Steel (MLS) construction for maximum durability and superior sealing
• .040" compressed thickness provides optimal sealing and compression control
• 4.580" bore diameter designed for GM/Mercury Marine Gen-IV big block engines
• Includes provisions for 2 slotted lifter valley bolts
• Advanced MLS technology accommodates cylinder bore distortion and head lift
• Embossed stainless steel layers with Viton rubber coating resist combustion gases and fluids
• Reusable design allows for multiple installations when properly torqued

Cometic MLS gaskets are the choice of professional engine builders and performance enthusiasts who demand reliable sealing under extreme cylinder pressures and temperatures. The multi-layer construction ensures consistent clamping pressure across the entire sealing surface while accommodating thermal expansion and minor surface imperfections.