Nowadays the development of new internal combustion engines is significantly growing in complexity because of the challenging targets set by the governments and by the customer on its pollutant emissions and performance respectively. Moreover, the huge number of competitors in the automotive sector forces car manufacturers to strongly reduce the lead time of their new product in order to maintain a satisfactory level of profitability. Therefore, the development of reliable and predictive simulation tools is becoming crucial to investigate a wide range of innovative technical solutions and to reduce the number of expensive experimental campaign. In such a framework the goal of this thesis is the development of a 3D CFD model capable to reproduce the in-cylinder phenomena of a high-performance Direct Injection Spark Ignition Engine.