<div class="htmlview paragraph">This paper describes the development and evaluation of an electronically controlled engine speed governor for use on gasoline engine Chevrolet and GMC medium- and heavy-duty trucks. An electronic controller monitors engine speed and operates a solenoid valve producing a tailored vacuum signal that controls throttle opening. The new governor system was evaluated with new and exacting definitions of spread, surge, overshoot, full load speed and reload. The electronic governor system shows driveability improvements over the old “spinner” system at slightly lower cost and improved durability. It also represents an industry “first” in the application of electronics to gasoline engine governors.</div>