Abstract: The present invention relates to a control system for use with an internal combustion engine connected to a load through a variable speed transmission. The instant system protects the engine and conserves fuel by automatically reducing the engine horse power when it is appropriate. The system includes a fuel valve connected to a source of fuel for affecting the rate of fuel delivered to the internal combustion engine for determining the power output of the engine. A temperature responsive control is connected to a portion of the internal combustion engine and is connected to the fuel valve to affect the fuel valve for regulating the rate of fuel delivered to the engine when the temperature of coolant in the internal combustion engine reaches a predetermined value. A speed responsive control is connected to a portion of a power train connected to the output of the engine and is connected to the fuel valve in series with the temperature responsive control.

Abstract: A vehicle performance sensor that monitors the operation of a vehicle and provides a shift point indicator to inform the vehicle operator when to shift the transmission. When the rotational output from the vehicle torque converter is not within the desired operating range of the transmission gearing, a signal will be generated to notify the operator by a visual indication that the transmission should be shifted and which gear should be selected.