Development of conceptual drive-by-wire ECU for electric vehicle conversion (EVC) can be designed by means of a low cost and time saving model based process. This is done by employing MATLAB scripted programs to systematically compute the power flow regime of the electric vehicle propulsion and response to dynamic loads. In this particular design, vehicle data and modification of simplified federal urban driving cycle (SFUD) were the two main inputs for driving simulation. As a result, the simulation was capable to predict various EVC characteristics and design parameters, such as driving range, torque-speed characteristics, and motor power usage. Output obtained from simulation were employed as design criteria to set up drive-by-wire software and ECU hardware functions, which are driving modes, torque set point for EVC electric propulsion in all four quadrants. EVC functions also have potential benefits in the improvement of vehicle drivability to suit a driver's individual preference.