In the report, numerical models are suggested and compared with data from an experiment with a VBIED (Vehicle Born Improvised Explosive Device, "car bomb") loaded with 400 kg of plastic explosive. The experiment was performed in the Älvdalen test range, Sweden 2006. In the test set-up, the VBIED was placed 6 m in front of a 20 m long protective wall with a height of 4 m and a thickness of 1.3 m. Two pressure gauges were located behind the wall at the distances 6 and 16 m, 1 m above ground. The gauges measured rather complex pressure-time histories comprised by the primary wave over the wall (increased by its reflexion on the wall's front side), its reflexion on the ground behind the wall and finally, the waves around the wall's side corners. The idea was to use this complex wave pattern to check the accuracy of the suggested numerical models of the VBIED. With the hydrocode Autodyn the protective wall with surrounding ground plane was modelled together with a large volume of air above. Different models of the charge were placed into the model of the surroundings, where pressure traces from simulated gauges were compared with the measured pressure traces from the experiment. The modelled charge was varied both by mass (TNT was used as an equivalent), by shape (half-spheres, short cylinders) and location (on ground, above ground). It was found that the best result was obtained with 340 kg TNT formed as a short cylinder with its height = half the diameter, placed with its mass centre 0.5 m above ground. The result indicates that a relatively small fraction of the energy, ca 10-20%, was absorbed by the material in the vehicle. It should however be noted that the tested VBIED contains a relatively large amount of explosive, 400 kg. For VBIED:s with less explosive inside, the energy losses has been reported to be about 50%.