The recent surge in the demand for the virtual application has led to the need for prototype testing that control the associated problem to a great extent. Consequently, a reduction in the costs of operating the actual prototype is envisaged. However, in some cases, just by adjusting input parameters alone could increase the success rate of these prototypes. During the design process, the functional prototyping is mainly used to evaluate the appearance of product and simulate its system level functioning. Multi-body dynamics analysis involves the simulation of rigid body systems under the application of forces or motions. Virtual prototype can substitute the physical prototype to perform a system level functioning of the product. The Internal combustion engine mechanism is considered for simulating the system level working with real time dynamic responses. Virtual prototype is created with a rigid body concept for an existing four stroke, single cylinder internal combustion engine mechanism to visualize the system level functioning and to find the displacement, velocity and acceleration of the piston on account of validation of the actual functioning of the engine. Virtual engine created by modeling individual parts of the product using CAD software and is simulated by using Hyper-Works computer aided engineering (CAE) tool. Finally, the validation of the functioning of the engine is done by comparing the results obtained by mechanism response (slider-crank mechanism; idealized for an internal combustion engine) of the engine using real time operating data collected experimentally.