The influence of some parameters, such as: engine hood, windshield and rear window slant angle, body taper, and base pressure, on the potential flow pressure distribution around an automotive vehicle is studied using potential aerodynamic panel code. The results are analyzed from physical arguments associated with potential flow approximation and compared to some available experimental data. Such approach would lead to some understanding on the validity of numerical potential aerodynamics for modeling and studying the influence of some geometrical parameters on the aerodynamic characteristics of automotive vehicles to be used for preliminary design purposes. In particular, the influence of base pressure on the aerodynamic characteristics of the vehicle is also studied and discussed. The potential flow results can be used to identify region of adverse pressure gradient, where separation is likely to occur.