4.12 MLS Head Gasket LH .040 Dodge 6.4L Hemi

The 4.12 MLS Head Gasket LH .040 Dodge 6.4L Hemi from COMETIC GASKETS is engineered for serious engine builders and mechanics tackling high-performance Hemi rebuilds or top-end repairs. This left-hand gasket addresses one of the most critical sealing points in modern Dodge performance engines, where factory tolerances and aftermarket modifications demand precision engineering. Whether you're freshening a stroker build, addressing a blown head gasket, or upgrading to tighter bore spacing, this Cometic unit delivers the reliability that professional shops and enthusiasts depend on.

Cometic's MLS (Multi-Layer Steel) construction uses a spring steel core with elastomer facing to create a conformable, leak-proof seal that handles both boost and heat cycling. The .040-inch thickness specification is critical for achieving proper clamp load and compression ratio control on the 6.4L platform, particularly when combined with modern cam packages, forced induction, or higher-octane fuel tuning. The gasket's ability to maintain sealing integrity under thermal and mechanical stress—essential for Hemi engines that run hot and hard—makes it superior to OEM compositions that can degrade after repeated heat cycles or aggressive tuning sessions.

This left-hand gasket is purpose-built for Dodge 6.4L Hemi applications requiring precision OEM or aftermarket head gasket replacement, including vehicles with upgraded cylinder heads, ported castings, or modified bore spacing. Installation requires proper torque sequencing and surface preparation—mating surfaces must be clean, flat, and within specification to realize the gasket's full sealing potential. Builders working with supercharged, turbocharged, or naturally aspirated high-compression builds will find this gasket indispensable for ensuring long-term durability and preventing coolant or oil weeping at the head-block interface.