Gaskets and Seals Engine Gaskets and Seals

Cometic Gasket

Cometic GM Gen-V/VI Big Block V8 .120in MLS Cylinder Head Gasket - 4.320in Bore

$276.93

SKU: C006 C5817-120

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In Stock
Ships by Jun 17
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Non-Returnable Item
INSTALL DIFFICULTY
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Easy — 1–2 hours

Description

The Cometic C5817-120 is a Multi-Layer Steel (MLS) cylinder head gasket designed for GM Gen-V/VI Big Block V8 engines. It features a compressed operating thickness of 0.120 inches and a bore size of 4.320 inches.

The gasket is constructed from multiple embossed layers of stainless steel, with the outer layers coated in Viton rubber for heat resistance up to 482°F. This design provides maximum sealing performance for high-output engines and is suitable for both aluminum-to-aluminum and aluminum-to-cast iron block configurations.

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Specifications

BrandCometic Gasket
Part NumberC006 C5817-120

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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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