Cometic 09+ GM LS9 4.100in Bore .051 thick MLX LHS Head Gasket

The Cometic 09+ GM LS9 4.100in Bore .051 thick MLX LHS Head Gasket is intended for the verified vehicle applications listed below. Match manufacturer part number C5986-051, exact engine family, bore, thickness, material, sealing surfaces, fasteners, and every product note before ordering.

Key Features

• Durability: Built to withstand the intense heat and pressure of the supercharged 6.2L LS9 engine, this gasket resists blowouts and maintains integrity even in the most aggressive builds.
• Engineering: With a 4.100-inch bore and 0.051-inch thickness, this gasket is tailored for optimal compression ratios, delivering maximum power output and efficiency.
• Bore Size: 4.100 inches.
• Material: Multi-Layer Xtreme (MLX) stainless steel with stopper layer.
• Performance: The MLX design features multiple layers of stainless steel with strategic embossments and a proprietary stopper layer, ensuring a robust seal that handles extreme boost pressures and high horsepower applications without compromise.

Fitment

Specifications

What’s Included

One new Cometic gasket product in the exact configuration and quantity identified by manufacturer part number C5986-051. Fasteners, sealants, fluids, companion gaskets, tools, and related engine components are included only when expressly stated for this exact part number.

About Cometic Gasket

Cometic develops sealing products for automotive and powersports engine applications. Correct selection remains exact-engine, exact-dimension, exact-material, exact-interface, and exact-part-number specific.

Related Cometic Gasket Products

• Cometic GM LS9/LSA Gen-4 Small Block V8 .040in MLX Cylinder Head Gasket 4.100in Bore LHS
• Cometic GM LS7 Gen-4 Small Block V8 4.150in Bore .040 Thick MLX Head Gasket
• Cometic GM LSX LHS 4.15in Bore .052 in MLX 5-Layer Head Gasket

Browse the Cometic Gasket collection for related head, intake, exhaust, valve-cover, and engine gasket products.

Frequently Asked Questions

Will this Cometic gasket fit my 2009-2015 Cadillac CTS V?
That application is listed, but confirm the exact engine, bore, gasket thickness, material, sealing-surface requirements, and manufacturer part number before ordering.

Can I choose gasket thickness by vehicle alone?
No. Confirm the exact engine build, bore, deck and head condition, installed clearances, compression target, and manufacturer instructions before selecting thickness.

Do the sealing surfaces need preparation?
Yes. Follow the current Cometic and engine-builder requirements for surface finish, flatness, cleanliness, fasteners, torque procedure, and any specified sealant.

Installation Instructions

Follow the current Cometic and engine-manufacturer instructions for this exact part number. Verify surface finish, flatness, cleanliness, orientation, fasteners, torque sequence, torque values, sealant requirements, clearances, and fluid procedures before assembly. Inspect and test the completed repair before full-load operation.