4.630 MLS Head Gasket .070 - BBC

The 4.630 MLS Head Gasket .070 by Cometic Gaskets is a precision-engineered cylinder head gasket designed specifically for big-block Chevrolet (BBC) engines that are undergoing high-performance modifications. This gasket is essential for sealing the combustion chamber under extreme pressure and heat cycles, effectively preventing coolant and oil leakage while maintaining compression integrity in various engine builds, including stroker, boosted, and naturally aspirated configurations.

Constructed from multi-layer steel (MLS), this gasket features three stainless steel layers bonded with elastomer, providing superior compressibility and sealing performance compared to traditional cork or composite gaskets. The .070-inch thickness is specifically engineered for engines with smaller chamber volumes or deck heights, allowing tuners to fine-tune compression ratios for specific fuel octane and boost levels. The 4.630-inch bore diameter aligns with BBC block specifications, and the MLS design resists deformation, chemical attack, and blow-by, making it critical for high fuel pressure, nitrous systems, or turbocharged applications.

This gasket is ideal for serious engine builders, performance shops, and automotive enthusiasts who demand repeatability and longevity in big-block builds. Proper installation requires adherence to head bolt torque sequencing and ensuring a clean deck surface, following manufacturer specifications to avoid potential issues during operation.