The 2004 Z4 did get four stars
Comments The Z4 is a very strong scoring four-star car. It suffered very little damage to its cabin, the driver’s door remaining straight and substantially undamaged after the impact. The car was tested in the frontal crash with its roof down to give ‘worst-case’ results. Similarly, for the side impact, the top was left up to check for any adverse interaction with the driver’s head. Because the car has only two seats, it was tested without child restraints. However, it is possible to fit a restraint to the passenger’s seat so, the fitting and labelling requirements were checked. Protection for pedestrians proved to be fair.
Front impact The restraint system is based on a dual stage non-tethered airbag for the driver and for the passenger. Each has a belt pre-tensioner that, combined with load limiters worked well at keeping forces on occupants’ chests low. Late in the impact, the driver’s head moved towards the outside of the airbag, making a glancing contact with the screen pillar. The car’s body proved itself to be very strong, showing minimal deformation of the body structure around the sill and screen pillar and suffering only minor intrusion into the footwell. However, the knee impact areas for the driver were unforgiving, with hard structures abounding. Side impact The protection system is very impressive and includes a thorax airbag that worked well. The driver’s head contacted the roof rail, but not hard enough to cause concern. Child occupant As two adult dummies were fitted no room remained for a child restraint. It is possible to fit one to the passenger’s seat. However, the only warning of the dangers associated with doing so was a text label on the windscreen, which was non-permanent and poorly worded. Pedestrian Levels of protection were fair. The bonnet’s leading edge did not require testing as its shape and low height meant that it would not be aggressive. Some areas of its top gave protection. But its sides, wings and the bumper, proved particularly unfriendly