Champion 791 C57YC Racing Spark Plug 14mm Gasket Seat

The Champion 791 (C57YC) is a high-performance racing spark plug engineered for engine builders, weekend racers, and street performance enthusiasts seeking to optimize engine performance. This professional-grade spark plug delivers the same reliable ignition used in many race cars and trucks.

Key Features:

• 14mm thread diameter with 0.750-inch (19mm) reach
• 5/8-inch (16mm) hex size for standard socket wrench access
• Copper-cored nickel alloy center electrode for increased conductivity and superior heat control
• Nickel alloy ground electrode for durability under extreme conditions
• Projected core nose design for improved flame kernel exposure
• Gasket seat style for secure sealing
• Non-resistor design for racing applications
• Heat range 57 (colder plug for high-performance engines)
• Pre-gapped at 0.026 inches (0.65mm)

Installation Specifications: Torque to 26-30 lb-ft for cast iron heads or 18-22 lb-ft for aluminum heads. Gap settings vary by application: methanol fuel typically requires 0.022-0.025 inches, while gasoline applications use 0.030-0.035 inches depending on ignition system output.

Cross-references to NGK R5672-10. Ideal for magneto-fired ignitions, sprint cars, late models, and aftermarket aluminum cylinder heads including Brodix applications.