A computerized 2 and 4 cycle internal combustion engine control and optimization/tuning system is disclosed, wherein fuel injector control is optimized to increase horsepower and fuel economy. The system is comprised of an on-board engine controller with communications software allowing technicians to change external sensors via an external computer. The technician may tune engine parameters on the fly as the engine is running. The engine control system displays engine-operating parameters in real time. Fuel mapping can be for the operator's choices of acceleration, maximum speed, gas mileage, altitude of operation and/or engine temperature.