A method and system for boosting a torque output of a drive train comprises an engine speed detector for detecting an engine speed of an engine having a baseline torque versus engine speed curve. A data processor determines if the detected engine speed is within a first range of engine speeds, if the detected engine speed is within the first range, the electric motor is activated to rotate substantially synchronously with the engine speed within the first range in an electric propulsion mode in accordance with a supplemental torque versus engine speed curve. The supplemental torque versus engine speed curve intercepts the baseline torque versus engine speed curve at a lower engine speed point and a higher engine speed point.