Cometic C9671 Copper Head Gaskets 3-5/8" Big Bore .020" Shovelhead 2-Pack

Cometic C9671 copper cylinder head gaskets are engineered specifically for big bore Harley-Davidson Shovelhead engines with a 3-5/8" (3.625") bore diameter. This 2-pack includes both left and right head gaskets with a .020" compressed thickness, providing precision sealing for high-performance applications.

Key Features:

• Premium 99.9% pure oxygen-free C110 copper construction for superior thermal conductivity
• 3-5/8" (3.625") big bore diameter designed for modified Shovelhead engines
• .020" compressed thickness for precise deck height control
• Fully annealed dead soft copper material that conforms to irregular surfaces
• Excellent heat dissipation properties reduce hot spots and prevent gasket failure
• Ideal for engines machined with O-rings for extreme cylinder pressures
• Sold as a matched pair (left and right cylinder head gaskets)

Cometic copper head gaskets are the preferred choice for serious builders working with high-compression or forced-induction Shovelhead engines. The soft copper material compresses easily during installation and creates a reliable seal on precision-machined surfaces. O-ring grooves are recommended for optimal sealing performance in high-boost or extreme racing applications.