New materials, such as elastic-plastic-brittle aluminum alloys and predominantly brittle-fracturing fiber reinforced plastic materials (composites) are a potential alternative to the conventional steel materials used in car body structures. While linear elastic stiffness, vibration and stress analyses pose no notable added difficulties, the crashworthiness simulation of structures and components made of composites or aluminum alloys must cope with the basic brittleness and fracturing behaviour of the material and with crash energy absorption modes that may be entirely different from the elastic-plastic crash energy absorbing folding modes, typically encountered in soft steel car body structures. A previous paper outlined a methodology that has been conceived, calibrated, validated and extrapolated for elastic-plastic-brittle and multilayered and multi-material composite sandwich wall and sandwich core models for the numerical crashworthiness prediction of composite components. The new models have been implemented into a crashworthiness simulation program, PAM-CRASH™, and validated on component crash tests. The effects of combining brittle carbon and plastic Kevlar fibers in the sandwich facings of the tested structures have been studied. In the present paper, the models are extrapolated to the numerical crash simulation of a full size composite passenger car cabin.