NGK Racing Spark Plug Box of 4 (UR4IX)

The iridium alloy's extremely high melting point makes these NGK UR4IX spark plugs a solid choice for engines that run hot. They feature a fine wire center electrode, which requires less voltage to ignite, helping with starting and idling. The tapered cut ground electrode is also designed to improve throttle response. These plugs are built with a pure alumina silicate ceramic insulator that offers superior strength and better heat transfer than standard materials, and the corrugated ribs on the insulator help prevent flashover. A copper core is included to aid in heat removal, and triple seals are used to prevent any leaks.

NGK Racing Series plugs are built to handle tough engine conditions, making them a good option for modified or high-performance applications, or simply as an upgrade over stock nickel alloy plugs. They are sold in a box of four, so you'll have enough for most common 4-cylinder engines, or you can mix and match for V-engines. These fit a wide range of vehicles, including many older Chevrolet, Buick, and Dodge models.