MSD Ignition is known throughout the world as the leader in performance ignition components for automotive applications. The MSD Circle Track Racing Ignitions for harsh racing applications such as stock cars, late models, and modifieds are designed specifically for circle track and severe duty racing applications. All of them feature: Powerful multiple sparks with 110 milliJoules of spark energy. Voltage delivered to the coil is 470 volts. Spark duration lasts for 20° of crankshaft rotation. Operates at full power with a supply voltage of 10 - 18 volts and will run down to 5 volts.