Take Care Of Your Work Horse This MSD governor is perfect for commercial vehicle application that operate under 5,000 rpm (i.e. delivery trucks). This soft touch governor will protect against missed shift or driveline failure and is a good feature for driver training applications. RPM limit is easily adjusted with supplied 3,000, 3,800 and 4,000 plug-in rpm modules. 50-state legal via E.O. #D-40-29.