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Cometic C5403-040 MLS Cylinder Head Gasket Chevy Small Block Bore - for V8 4.200 040

(GMC G2500 1979-86, K1500 1979-86, C1500 1979-86, K2500 1979-86, Jimmy 1970-86, C3500 1979-86, K2500 Suburban 1979-86, K3500 1979-86 + 168 more models)

Part of: Cometic MLS Cylinder Head Gasket Bore Chevy Small Block

Other options in this family: Cometic C5245-040 Cometic C5269-040 Cometic C5403-051 Cometic C5246-051 Cometic C5248-080

Manufacturer

Picture for manufacturer Cometic

Part Number

C5403-040
18 reviews
Sale Price

$93.12

In Stock (8)

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Usually delivered within 2 days

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Product Details

The Cometic C5403-040 is a high-performance Multi-Layer Steel (MLS) cylinder head gasket engineered specifically for Chevrolet Generation I small block V8 engines with aftermarket cylinder heads. This .040" thick gasket features a 4.200" bore diameter and incorporates undersized water ports that allow engine builders to customize coolant flow for their specific application.

Key Features:

  • Multi-Layer Steel (MLS) construction provides superior sealing and durability under extreme combustion pressures
  • 0.040" compressed thickness for precise compression ratio tuning
  • 4.200" bore diameter accommodates stock and slightly overbored small block Chevy engines
  • Undersized water ports enable custom port matching to aftermarket cylinder heads
  • Designed specifically for aftermarket performance heads on Gen-1 SBC applications
  • MLS technology eliminates the need for sealants and resists gasket failure from thermal cycling

Cometic's MLS gaskets feature multiple layers of stainless steel with advanced coating technology, making them ideal for high-performance street engines, race applications, and boosted combinations. The undersized water port design gives engine builders complete control over coolant flow optimization when using aftermarket heads with varying port configurations.

Products specifications

Fits

GMC G2500 1979-86, K1500 1979-86, C1500 1979-86, K2500 1979-86, Jimmy 1970-86, C3500 1979-86, K2500 Suburban 1979-86, K3500 1979-86, C15/C1500 Pickup 1967-74, C2500 1979-86, K1500 Suburban 1979-86, G25/G2500 Van 1967-74 + 164 more models

Prop 65

WARNING: Cancer and Reproductive Harm - www.p65warnings.ca.gov

Material

Multi-layer Steel

Overall it turned out good .

Great service

Fast, Easy and free shipping

Good

I will look here again when I need something.

Great service and quick

Fast Shipping!

It's smaller than it should be but said it fit my year/make/model for my Jeep

fast and easy to find the parts I need thank you

They had the lowest price by far! Quick shipment! I am going back for more. Thanks!<br><br>Order 6489

Great pricing!! cheapest products on the web!

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I really like how prompt the order went through and the quality of the part im getting

Great place to shop online. The best price on the internet and super fast delivery. Shop with Autoplicity, highly recommended.

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I only gave them a 3 star raring on their shipping because I went on their site on Tuesday and the order said it had not been shipped. On Wednesday I received my shipment. The left hand needs to figure out what the right hand is doing. Other than that, GREAT

Fast shipping and good prices. I would shop this site again.

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