摘要 |
A spark advance and retard system for an automobile engine advances the spark timing when the automobile is cruising, and retards the spark timing when the automobile is idling, accelerating or decelerating. A device which detects cruising of the automobile employs three electrical switches connected in series: the first is opened by actuation of the automobile brake pedal, the second is closed by actuation of the accelerator pedal, and the third is closed by high vacuum conditions in the engine intake system. When all three switches have been closed for a predetermined time interval, a timer device actuated electrically controlled valves to cause a pneumatic operator to advance the spark timing. |