Pertronix Flame-Thrower HEI III 4-pin ignition modules feature multiple Sparks through the entire rpm range, plus an integrated high resolution Digital Rev-Limiter. The rev-Limiter settings are displayed with a led feedback for precise rpm settings. adaptive dwell maintains peak Energy Throughout the entire RPM Range, reducing misfires While improving engine Performance. peak current level is rEached just prior to Spark for maximum Energy without the heat build-up, increasing Coil Performance and module reliability. The Pertronix Flame-Thrower HEI III 4-pin ignition modules adjusts Spark timing at higher rpms to compensate for the inherent electronic delay and they can sense startup and increases Energy for quicker, easier starting.