his own blog post from January 2016, the Vauxhall VX220 used in the images didn't actually have an engine so was towed to the various nighttime cityscape locations used as backdrops:
"Apparently the car used in the photoshoot didn't have an engine so had to be dragged to various shooting spots. In one of the slides you can see some of the rigging at the rear of the car, I'm guessing it was pulled backwards and snapped with a slow shutter to give the illusion of speed."
- Blue Swirl
You can also find further confirmation of these claims on the site of Rosco, the artist who actually worked on this project for Sega Europe. These images may not seem like much, but to know that the original slides and negatives are still in existence and now in the hands of a Dreamcast collector like Blue Swirl is very reassuring. In essence it means that they'll not only be enjoyed as the slice of Dreamcast history that they are; it means they'll be preserved for posterity for years to come.
Source: Blue Swirl (all images used with permission)