In this search, the automotive engine (includes four cylinders and eight valves) is analyzed. The procedure is: (1) building the CAD models of engine mainframe; (2) assembling the components in bottom-up mode; (3) assign the mechanical properties of each component, e.g. mass, young's modulus, coefficient of thermal expansion, etc. As for the analysis items, there are three parts: (1) motion analysis of four-stroke engine; (2) static and dynamic states of mechanism; (3) thermal analysis. Based on the above data to compare with the standards in automotive market for verify the design availability.