Cometic C5986-040 GM MLS Head Gasket Bore - LS9/LSA Gen-4 V8 4.100 040

The Cometic C5986-040 is a high-performance Multi-Layer Steel (MLS) cylinder head gasket engineered specifically for GM LS9 and LSA Gen-4 small block V8 engines. This .040" thick gasket features a 4.100" bore diameter and is designed for the left-hand side (LHS) cylinder head application.

Key Features:

• Multi-Layer Steel (MLS) construction for superior sealing and durability
• .040" compressed thickness for precise compression ratio tuning
• 4.100" bore diameter optimized for LS9/LSA applications
• Advanced coating technology prevents corrosion and improves seal
• Engineered to withstand extreme cylinder pressures in forced induction applications
• Embossed stainless steel layers provide multiple sealing points
• Allows for proper deck surface flexing while maintaining seal integrity

Cometic MLS gaskets are the preferred choice for high-performance and racing applications where reliability under extreme conditions is critical. The multi-layer design with embossed beads around combustion chambers, coolant passages, and oil passages ensures consistent clamping pressure and exceptional sealing. This gasket is ideal for supercharged LS9 and LSA engines found in Corvette ZR1 and Cadillac CTS-V applications, as well as performance builds requiring precise head gasket thickness selection.