What is the compressed thickness of this head gasket?

The compressed operating thickness of this Cometic head gasket is 0.070 inches. This measurement is important for ensuring the correct compression ratio and valve-to-piston clearance in your engine build.

Can I use this gasket with aluminum heads and a cast iron block?

Yes, this Multi-Layer Steel (MLS) gasket is designed to work with aluminum heads on both aluminum and cast iron blocks. The construction helps manage the shearing forces that can occur between these different materials.

What does 'undersized water ports' mean for installation?

The undersized water ports mean that the openings for coolant on the gasket are slightly smaller than the final desired size. This allows you to machine or port them to perfectly match your specific aftermarket cylinder heads, ensuring optimal coolant flow and sealing.

Specifications

Brand: Cometic Gasket
Part #: C5403-070
UPC: 191070075767

Cometic Chevrolet Gen-1 Small Block V8 .070in MLS Cylinder Head Gasket - 4.200in Bore

Name: Cometic Chevrolet Gen-1 Small Block V8 .070in MLS Cylinder Head Gasket - 4.200in Bore
Brand: Cometic Gasket
SKU: cometic-gasket-cometic-chevrolet-gen-1-small-block-v8-070in-mls-cylinder-head-ga-t14-805610
Price: 131.62 USD
Availability: BackOrder

$131.62

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Cometic Chevrolet Gen-1 Small Block V8 .070in MLS Head Gasket - 4.200in Bore. Built with multiple stainless steel layers and Viton coating for reliable sealing.

Key Features

Fits 56+ vehicle make/model combinations.
Multi-Layer Steel (MLS) construction offers increased strength and corrosion resistance.
Outer layers are coated with Viton, a heat-resistant elastomer, for reliable sealing.
Compressed operating thickness is 0.070 inches.
Designed for a 4.200-inch bore.
Features undersized water ports for customization with aftermarket heads.

⚠️ 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 your Chevrolet Gen-1 Small Block V8, getting the head gaskets right is crucial for sealing combustion and coolant passages. This Cometic Multi-Layer Steel (MLS) head gasket is built to handle the demands of high-output engines, offering a solid seal without needing extra sealants. It's designed for a 4.200-inch bore and has a compressed thickness of 0.070 inches.

Cometic constructs these gaskets from multiple layers of stainless steel, which gives them strength and helps them resist corrosion. The outer layers are coated with Viton, a heat-resistant rubber material that can handle tough sealing environments and different surface finishes. The center layer is also stainless steel and can be varied in thickness to meet specific build requirements. These gaskets are suitable for use with aluminum heads on both aluminum and cast iron blocks, as they can manage the shearing forces that can occur between dissimilar metals.

This gasket is specifically noted for its undersized water ports, which allow for customization when used with aftermarket heads. It fits a wide range of vehicles from the early 80s, including models like the Chevrolet Camaro, GMC C1500, and Buick Regal, among many others. Always refer to the manufacturer's installation instructions for proper torque sequences and procedures.