Automotive vehicles today consist of very complex network of electronic control units (ECU) connected with each other using different network implementations such as Controller Area Network (CAN), FlexRay, etc. There are several ECUs inside a vehicle targeting specific applications such as engine, transmission, body, steering, brakes, infotainment/navigation, etc. comprising on an average more than 50 ECUs executing more than 50 million lines of software code. It is expected to increase exponentially in the next few years. Such complex electric/electronic (E/E) architecture and software calls for a comprehensive, flexible and systematic development and validation environment especially for a system level or vehicle level development. To achieve this goal, we have built a virtual multi-ECU high fidelity cyber-physical multi-rate cosimulation that closely resembles a realistic hardware based automotive embedded system. It consists of two inverter/motor control virtual ECUs and a CAN router ECU coupled with abstracted real vehicle level CAN traffic emulation. Such a multi-ECU system simulation would enable system design optimization by allowing virtual experimentation and comparison of different E/E architectures with respect to the number of ECUs, performance as well as the choice of microcontroller and hardware components. This virtual implementation methodology is exhaustive to potentially support a vehicle level simulation that would enable component, system and vehicle level software development very early in the design phase and drastically reduce the overall development time for the vehicle.