Considering the recent advances in autonomous driving technology, conventional on-road based testing tools cannot meet the validation requirements with respect to time and cost-efficiency. Scenario-based virtual validation methods offer an efficient virtual testing approach that supports the development and contribute to decreased on-road-testing. X- in-the loop testing methods contribute to stepwise increase in test/validation quality by introducing hardware/software elements starting from the component up to full vehicle level and have been increasingly integrated into the process of design and validation of intelligent vehicle systems. In this paper, a novel framework that includes a highly dynamic vehicle-in-the-loop test bed, a traffic flow simulation method is introduced to precisely assess the impact of specific variables on the performance of an intelligent system with all vehicle components included.