4.200 MLS Head Gasket .040 - SBC

The Cometic Gaskets 4.200 MLS Head Gasket .040 for Small Block Chevy (SBC) is a multi-layer steel cylinder head gasket engineered for engine builders and performance enthusiasts who demand precise compression sealing and reliable long-term performance. This gasket delivers the critical interface between cylinder head and block where combustion pressure, coolant flow, and oil passages must remain perfectly sealed under extreme operating conditions. The .040-inch compression thickness and 4.200-inch bore size are specified for particular SBC applications where factory or performance-level compression ratios require exact gasket geometry to maintain intended engine dynamics.

Multi-layer steel (MLS) gasket construction provides superior durability compared to conventional single-layer designs. The layered steel composition resists blowout, maintains clamp load consistency across thermal cycling, and tolerates surface finish variations on aged or resurfaced cylinder heads. The .040-inch thickness is a critical specification—too thin and combustion pressure escapes; too thick and it alters compression ratio and timing relationships. Proper installation requires torque specifications matched to your engine builder's technical data, as head bolt torque directly affects gasket performance and longevity.

This gasket is intended for engine assembly, rebuild, or repair work on Small Block Chevy platforms—common in street performance, racing, marine, and industrial applications. Whether you're rebuilding a classic muscle car engine, assembling a stroker package, or restoring a reliable daily driver, the correct head gasket specification is non-negotiable for reliable sealing. Cometic Gaskets has established credibility in the performance engine community for consistent quality and attention to dimensional tolerances that prevent post-installation problems.

Before installation, verify that the 4.200-inch bore and .040-inch thickness match your engine's technical specifications. Cylinder head and block surfaces must be clean, smooth, and properly prepared per Cometic's installation guidelines. This is a single gasket unit sold individually—verify your engine requires one gasket per head and order accordingly for complete engine assembly.