Cometic Engine Cylinder Head Gasket
Cometic C9721-036 MLS Head Gasket Kit for Harley Twin Cam 3.875" Bore .036" Thickness
Cometic C9692-036 HD Stainless Steel Head Gasket Set Evolution Motors .036" 2-Pack
Cometic C9691-030 HD Stainless Steel Head Gasket 3.670" Bore EVO .030" 2-Pack
Cometic C9689-3570-040 HD Evolution Stock Bore 3.570" Head Gasket Set Stainless Steel .040" 2-Pack
Cometic C9689-075 MLS Head Gasket Set Harley Evolution Bore Thick - 3.500 075 2-Pack
Cometic C9689-056 MLS Head Gasket Set for Harley Evo 3.500" Bore .056" Thick 2-Pack
Cometic C9689-054 MLS Head Gasket Set Harley Evolution Bore Thick - 3.500 054 2-Pack
Cometic C9689-050 MLS Head Gasket Set for Harley EVO Big Twin 3.500" Bore .050" 2-Pack
Cometic C9791-040-020 Millennium Cylinder Head & Base Gasket Kit 3-9/16" Bore
Cometic C9791-040 Millennium Head & Base Gasket Kit 3-9/16" Bore .040" H/G .018" B/G
Cometic C9743-UE MLS Cylinder Head Gasket Set 4.125" Bore .040" Harley Twin Cam
Cometic C9863-HB-040 Head & Base Gasket Kit Buell Blast Big Bore 3-13/16" .040"
Cometic C9880-051 MLS Head Gaskets 4.0" Bore .051" S&S TP Harley Evolution (Pair)
Cometic Cylinder Head Gaskets: Engineered for Extreme Sealing
When it comes to keeping combustion where it belongs, few names carry the weight that Cometic does in the world of high-performance engine sealing. Their engine cylinder head gaskets are the product of decades of motorsport development, precision materials science, and real-world validation on racetracks across every major sanctioned series. Whether you're building a street-driven performance machine or a dedicated racing engine, Cometic's head gasket lineup offers a technology tier matched to your exact application.
Three Distinct Technology Tiers
Cometic's cylinder head gasket catalog is organized around three core material technologies, each engineered for a specific range of sealing demands:
- MLS (Multi-Layer Steel): The foundation of Cometic's head gasket lineup. MLS gaskets are constructed from multiple layers of stainless steel, with load-controlled embossments that help distribute clamping force evenly across the sealing surface. The stainless outer layers feature a rubber-binder coating made from high-temperature and chemical-resistant polymers, creating a reliable combustion seal that requires no additional sealants or re-torque when installed on properly prepared surfaces.
- MLX (Multi-Layer Xtreme): Cometic's MLX gaskets add a precision fold-over stopper layer to the MLS architecture. This stopper design improves clamp-load concentration and provides local stress and sealing integrity around the combustion chamber without increasing bore distortion — making it ideal for boosted, nitrous, or high-compression builds.
- DST (Dual Stopper Technology): Cometic's newest and most extreme design, the DST uses a seven-layer construction featuring two integrated stainless steel stopper layers folded directly into the stack. When the head is torqued down, those stoppers create a concentrated ring of pressure around the bore, making DST the go-to solution for engines targeting 1,500+ horsepower. Current applications include Gen-III Hemi, GM LS, and GM LT platforms.
Precision-Engineered for a Wide Range of Applications
Cometic head gaskets span an enormous breadth of domestic and import platforms. From classic small-block Chevrolet and Ford applications to modern turbocharged engines from Nissan, BMW, Subaru, Honda, Hyundai, and Toyota, the catalog is continuously expanding. Cometic's HP (High Performance) gaskets also incorporate an optional shim layer that can be added to increase active seal height, while the center layer thickness of MLS designs can be varied to achieve precise compression ratio targets across a wide range of compressed thicknesses.
A critical advantage of Cometic's MLS and MLX construction is their suitability for mixed-material pairings. MLS gaskets are ideal for both aluminum heads on aluminum blocks and aluminum heads on cast iron blocks, handling the differential thermal expansion between dissimilar metals that has historically challenged traditional composite gaskets.
Race-Proven, Continuously Evolving
Cometic's involvement in championship-caliber motorsports — from NASCAR to NHRA — has driven the development of head gasket designs that are proven in the most demanding conditions imaginable. That same technology flows directly into every gasket available for street and performance builds. Cometic's in-house engineering team uses state-of-the-art design software and maintains in-house dynamometers to validate new applications before they reach the market, ensuring each gasket is drawn and manufactured to meet the precise demands of its intended engine environment.
Browse the full selection of Cometic engine cylinder head gaskets to find the right MLS, MLX, HP, or DST gasket for your build, or explore the complete Cometic brand catalog for full top-end kits and additional engine sealing solutions.