The multi-material chassis show how the split frame concept can be applied to extreme sport cars, with benefits in terms of weight reduction and performance. In the “Split frame architectures” the car body is divided into two distinct parts, lower and and upper. The first  one is a self standing chassis that carries all the engine and suspensions attachments and bears road and crash  loads. The upper part carries the passengers and give the external shape to the vehicles. The frames are connected by elastic mounts in order to ensures a high level of insulation from vibrations. This architecture is  not considered very efficient for high performance vehicles because of its weight, generally greater than a unibody solution. The “multimaterial chassis  project”  has demonstrated  that the previous  sentence can be rejected with a proper design ao the lower frame, that use the right material, technologies and shape  for each sub group. As a result, the structure makes use of titanium alloys, aluminum (both cast and extruded members) and carbon fibers,. The whole chassis weight is under 100 Kg, and its performances (crash requirements and torsional stiffness)  are adequate for extreme sport cars.