4-Cycle Spark Plug

The Bosch F8DC4 is a conventional nickel-copper spark plug engineered to deliver a balance of performance and value. It utilizes a heavy-duty, yttrium-enhanced nickel center electrode with a copper core, offering increased durability and a 50% longer performance life compared to standard copper plugs. The copper core itself provides a broader heat range, which helps to resist pre-ignition and fouling, ensuring consistent operation. Key specifications include a 14mm thread diameter with a 1.25mm pitch, a 19mm reach, and a 16mm hex size. The gap size is pre-set at 0.8mm (0.031 inches). This non-resistor plug features a flat seat type and a non-projected insulator. Bosch's design also incorporates an angled, ribbed insulator to prevent misfires caused by flash-over, and a metal glass-fused resistor to maximize interference suppression. The F8DC4 spark plug is intended for 4-cycle applications and is engineered to meet or exceed Original Equipment (OE) specifications.