The Splitfire "V" design in the ground electrode is instrumental in helping to improve combustion efficiency. Because the flame kernel isn't blocked by the ground electrode, it can travel through the "V" notch into the combustion chamber. Copper core aids in cooling. Power tip projects the firing tip into the combustion chamber for maximum exposure to the air/fuel mixure. Smooth ceramic insulator to insure a tight seal at plug boot. Resistor plugs minimize electronic interference and can aid in reducing electrode erosion. 14MM .750"REACH 5/8"HEX Clearance! NO WARRANTY, NO RETURNS ON GARAGE SALE ITEMS
