Most composite components are constructed in a very safe way, with thick walls and many laminate layers. The potential of lightweight construction will not be fully tapped. In a typical computation of the behavior of a component, the wall thickness and fiber directions have to be entered into the simulation system. The result is the load-dependent deformation of the component. That approach takes a lot of time to get an optimized construction. A better way for optimizing fiber-reinforced composites is the use of simulation algorithms to get an optimal material distribution. In this case, the simulation output shows the optimal layer thickness and fiber directions for every node depending on the selected maximum deformations and the load of the structure. This method was used to reduce the weight of the special, extremely energy-saving vehicle called “Sax 3” of the student project “fortis saxonia” for the Shell Eco-marathon 2008. Thus it has become possible to keep the weight of the chassis of the vehicle under 10 kg. This shows the high potential of the implementation of this optimization approach for fiber-reinforced composites.