NGK 6431 BU8H
Surface gap plugs are nearly immune to pre-ignition, and usually require a special high energy ignition system. They can be susceptible to fouling, especially in colder applications, but may be necessary in high compression applications.
Trivalent metal plating provides superior anti-corrosion and anti-seizing properties
Corrugated ribs prevent flashover
Pure alumina silicate ceramic insulator, provides superior strength and better heat transfer
Copper core aids in heat removal
Triple seals prevent leakage
Shell
Thread Diameter: 14mm
Thread Pitch: 1.25mm
Seat Type: Gasket
Reach: 12.7mm (1/2")
Hex Size: 13/16" (21mm)
Terminal Type: Solid
Overall Height: ISO
Gap: .016" (0.4mm)
Center Electrode
Material: Nickel
Type: Standard
Size: 2.5mm
Projection: Non-Projected
Ground Electrode
Material: Nickel
Type: Surface Discharge
Specifications
Resistor: No
Resistor Value: 1K Ohm
Heat Range: 8
Torque Specs: Cast Iron: 18-25.3 lb. ft. Aluminum: 18-21.6 lb. ft.