Application Engineering of a Maintenance-Free Capacitor Discharge Ignition System

An ignition system with a 3500 h life capability has been developed for tactical military vehicles. An extensive test program was used to develop a capacitor discharge ignition system, composed of a capacitor energy storage system, a noncontacting metal detector timing system, a special coil, shielded ignition cable, and surface gap spark plugs. It provides ignition performance advantages, a single spark plug heat range, and is compatible with 4-, 6-, and 8-cyl military engines. The characteristics of various ignition systems were studied on the bench and on the dynamometer over a wide range of engine operation. The final design's capability to provide engine performance equivalent to the standard system was verified. The advantages and disadvantages of each ignition type is discussed.