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Cometic C5640-120 GM Mercury Marine Gen-IV Big Block MLS Head Gasket Bore - V8 4.580

Manufacturer

Picture for manufacturer Cometic

Part Number

C5640-120
8 reviews
Sale Price

$231.78

Estimated ship date Friday, November 27

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Product Details

The Cometic C5640-120 is a high-performance Multi-Layer Steel (MLS) cylinder head gasket engineered specifically for GM and Mercury Marine Gen-IV 1050 cubic inch big block V8 engines. This precision gasket features a .120" (3.0mm) compressed thickness and accommodates a 4.580" bore diameter, making it ideal for high-output marine and performance applications.

Key Features:

  • Multi-Layer Steel (MLS) construction provides superior sealing and durability under extreme cylinder pressures
  • Designed for GM/Mercury Marine Gen-IV big block V8 engines (1050 cubic inch displacement)
  • .120" compressed gasket thickness for precise compression ratio tuning
  • 4.580" bore diameter accommodates stroker and oversized bore applications
  • Includes 2 slotted lifter valley bolt holes for proper engine assembly
  • MLS design allows gasket to recover and maintain seal integrity through thermal cycling
  • Engineered to handle high boost and extreme combustion pressures in marine and performance builds

Cometic's MLS gaskets feature multiple layers of stainless steel with proprietary coatings that provide exceptional conformability to sealing surfaces. This construction ensures reliable sealing in demanding marine environments and high-performance applications where durability and consistency are critical.

Products specifications

Prop 65

WARNING: Cancer and Reproductive Harm - www.p65warnings.ca.gov

Material

Multi-layer Steel

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