4.040 MLX Head Gasket .051 GM LS1/LS2/LS3/LS6

The 4.040 MLX Head Gasket .051 GM LS1/LS2/LS3/LS6 from Cometic Gaskets is a precision cylinder head gasket engineered for GM's legendary LS-series engine platform. This gasket is purpose-built for high-performance LS applications where reliability and consistent sealing are non-negotiable. Whether you're rebuilding an LS1 from a C5 Corvette, refreshing an LS3-powered truck, or restoring an LS6 Z06, this gasket delivers the durability and precision fit that OEM and performance builders demand.

Constructed from multi-layer steel (MLS) material, the 4.040 MLX Head Gasket features a 0.051-inch compression thickness that maintains proper combustion chamber sealing while supporting modern boost levels and aggressive tuning. The MLS construction provides superior conformability to both stock and ported cylinder heads, reducing the likelihood of gasket blowout at the bore edge—a critical consideration in forced-induction and high-compression builds. The 4.040-inch bore diameter is precisely matched to LS-series head specifications, ensuring optimal clamping force distribution and eliminating radial stress that can compromise seal integrity.

This gasket is ideal for engine builders, performance enthusiasts, and technicians working on LS powerplant restorations, turbo conversions, or naturally aspirated rebuilds. The .051 thickness is compatible across LS1, LS2, LS3, and LS6 platforms, making it a versatile choice for mixed-generation builds or direct replacements. Installation requires proper head bolt torque sequencing and adherence to manufacturer specifications; Cometic recommends using quality fasteners and following the engine builder's torque curve for optimal results. Each gasket ships individually and is ready for immediate application.