What is the purpose of the Viton coating on the outer layers?

The Viton coating on the outer layers of the gasket is a heat-resistant rubber material. It's designed to meet the demands of harsh sealing environments, load conditions, and surface finishes, ensuring a reliable seal.

Why do these gaskets have undersized water ports?

The undersized water ports are a feature specifically for aftermarket heads. This allows for customization during installation to precisely match the water passages, ensuring optimal coolant flow and sealing.

Do I need to use any sealant with this head gasket?

No, Cometic MLS head gaskets are designed to provide maximum sealing performance on their own. They do not require any additional sealants for proper installation and function.

Specifications

Brand: Cometic Gasket
Part #: C5434-066
UPC: 191070089115

Cometic Chevrolet Mark-IV - GM Gen-V/VI Big Block V8 .066in MLS Cylinder Head Gasket - 4.630in Bore

Name: Cometic Chevrolet Mark-IV - GM Gen-V/VI Big Block V8 .066in MLS Cylinder Head Gasket - 4.630in Bore
Brand: Cometic Gasket
SKU: cometic-gasket-cometic-chevrolet-mark-iv-gm-gen-v-vi-big-block-v8-066in-mls-cyli-t14-803746
Price: 141.79 USD
Availability: BackOrder

$141.79

On Backorder

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Cometic Chevrolet Mark-IV, GM Gen-V/VI Big Block V8 .066in MLS Head Gasket - 4.630in Bore. Built for high output engines with aftermarket heads.

Key Features

Fits a wide range of Chevrolet Mark-IV and GM Gen-V/VI Big Block V8 engines.
Multi-Layer Steel (MLS) construction offers increased strength and corrosion resistance.
Outer layers are embossed and coated with heat-resistant Viton rubber.
Compressed operating thickness is 0.066 inches.
Bore size is 4.630 inches.
Designed for high-output engines and requires no sealants.

⚠️ CA WARNING: This product can expose you to chemicals known to the State of California to cause cancer and/or birth defects or other reproductive harm. Learn more

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About this part

Product Details

If you're rebuilding the top end of a Chevrolet Mark-IV or GM Gen-V/VI Big Block V8, especially with aftermarket heads, this Cometic Multi-Layer Steel (MLS) head gasket is a solid choice. It's designed to handle the demands of high-output engines, offering a reliable seal without needing extra sealants. This gasket is built to work with both aluminum and cast iron blocks and heads, resisting the shearing forces that can occur between different metals.

This gasket features multiple layers of stainless steel for increased strength and corrosion resistance. The outer layers are coated with Viton, a heat-resistant rubber material that can handle tough sealing environments and various surface finishes. The center layer is stainless steel and can be varied to achieve different thicknesses; this particular gasket has a compressed operating thickness of 0.066 inches and a bore size of 4.630 inches. It's also noted for having undersized water ports, which allows for customization when used with aftermarket heads.

This gasket fits a wide range of vehicles, including popular models like the Chevrolet Impala, Corvette, and C10 Pickup from various years. It's a well-built component designed for performance and durability in demanding applications.