In the initial design stage of a new car, designers need a lot of information about stress distribution, vibrational and thermal problems, interaction between engine and acoustic cavity, internal and external aerodynamic behaviors. This information must be available during the early pre-engineering phase to allow the design of optimized prototypes. A quick answer and clear result of presentation are very important elements that make it possible for the designer to act quickly and without any doubt. To reach this goal, it is essential to use specialized pre-and post-processors which check and interpret input and output data for Finite Element Method program systems. This paper shows the results obtained from several FEM analysis where the results of presentation was done using a 3D interactive graphics system.