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Mr. Gasket

Mr. Gasket Ultra-Seal Valve Cover Gaskets - .312 Inch Thick

Fits 1965-2000 Chevrolet 396-572 Mark IV/V/VI Big Block

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These are high quality gaskets that works well on those hard to seal applications. The low density fiber & rubber blend gasket material seals those minor head imperfections with a low clamp force. At .312 inch, the extra thickness can also offer slightly more clearance for roller rockers. Ideal for all those high performance applications where you take the valve covers off and on a lot, and sticking is a problem.

Fits all 1965-2000 Chevy Big Blocks: 366,396,402,427,454 including GM (General Motors) Gen VI Crate Engines like the 502 and 572.


  • These Are A Cork Rubber Blend
  • Extra Thick 5/16 In Creates Positive Seal
  • Also Available In Standard Thickness
  • For OE Replacement And High Performance Apps

About Mr. Gasket

Using his own '57 Chevy as a rolling testbed, drag racer Joe Hrudka launched the most famous gasket company in the world more than half a century ago. Mr. Gasket is the go-to gasket source for racers with gaskets and fasteners that seal perfectly every time.

ApplicationBig Block Chevy
Brand Mr. Gasket
Emission Code5
EngineChevrolet Big Block Gen V/VI
Chevrolet Big Block Mark IV
FinishRubber coated
PackagingRetail - Skin Pack
Product TypeValve Cover Accessories
Valve Cover Gasket MaterialUltra Seal
Valve Cover Gasket Thickness.312"
WarrantyLimited 90 Day Warranty
Part Number5863

This part is legal for sale or use on Emissions Controlled Vehicles, Uncontrolled (Non-Emissions Controlled) Vehicles, and Racing Use Only Vehicles because it does not affect vehicle emissions and is not covered by emissions regulations.

Limited 90 Day Warranty: See Details

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    *Free Shipping & Handling only offered to the contiguous US on orders over $100, excludes clearance parts and oversized packages.

    Some parts are not legal for use in California or other states with similar regulations.

     X  Holleydays 2021
     X  Holleydays 2021