MSD 37364 Iridium Tip Spark Plug Reach Gasket Seat - 14mm 0.500in 4-Pack

The MSD 37364 Iridium Spark Plug is a high-performance iridium-tipped spark plug engineered to maximize combustion efficiency and deliver increased durability in high-output ignition applications. Sold as a 4-pack with a 14mm thread size, 0.500-inch reach, and gasket seat, these plugs carry the MSD plug number 13IR6Y.

MSD designed these iridium spark plugs from the inside out, drawing on decades of experience in top fuel drag racing, endurance stock car racing, and off-road competition to deliver a plug that performs under the most demanding conditions.

Key Features:

• Iridium Center Tip: The center electrode tip is made from iridium — an extremely hard, wear-resistant material — to promote a consistent, reliable spark and exceptional longevity under high-output ignition systems.
• Proprietary Ceramic Insulator: A specially formulated ceramic material enhances the dielectric strength of the plug housing, ensuring the spark fires across the gap to the ground electrode even under extreme cylinder pressures.
• Machined Ground Electrode with Yttrium: The machine-ground strap is enhanced with Yttrium to withstand the intense heat generated by high-horsepower ignition systems, outperforming standard electrode materials.
• Copper Center Core: An engineered copper center core efficiently transfers heat away from the insulator tip and into the cylinder head, helping to prevent knock and extending plug service life.
• High-Performance Design: Specifically designed for use on high-performance vehicles equipped with high-output ignition systems, including MSD's own ignition products.
• Emissions Compliant: Holley/MSD Emission Code 2 — legal for sale and use on emissions-controlled vehicles when installed per the manufacturer's application guide.

The MSD 37364 iridium spark plug delivers the reliability and performance demanded by serious enthusiasts. With a plug design engineered for efficient combustion and long service intervals, these plugs are well-suited for street, strip, and off-road applications. Each pack includes 4 plugs. MSD part cross-reference: 13IR6Y.