Accel Spark Plug Accel U-Groove

ACCEL U-GROOVE PERFORMANCE SPARK PLUG -- 14 mm thread size, 0.708 in. reach, 5/8 in. wrench diameter, heat range 6; Resistor type, copper electrode core/tip material, projected insulator type, tapered seat style; Constructed with a five-rib, highly purified Alumina insulator that prevents arcing at plug boot and provides superior strength and thermal conductivity, a copper-glass seal that bonds insulator to electrode for a gas-tight seal, and a copper-core center electrode that comes with nickel chrome sheel for superior electrical conductivity and maximum heat dissipation; Its electric heat seal ensures stable heat range for uniform performance; The plug's machine rolled threads guarantee trouble free installation and removal, protecting the expensive cylinder heads; Features a unique U-groove ground electrode developed to meet the demand for improved ignitability and increased fuel combustion resulting in less flame dissipation; Gives the flame a groove to grow in that creates a larger flame front for a more complete combustion even in the case of lean air-fuel mixture; Produces greater firing energy without increasing spark plug gap and larger spark nucleus that stimulates faster combustion; Provides an increase in performance with improved throttle response, greater fuel efficiency and reduced emissions; With 90-day Accel limited warranty.