Wow. I love being reminded of stuff like this. Those cars were so cool.
Edit: I took one of these cars apart as a kid to see how it worked. This site brought back a lot of memories. The little coil spring inside the gear. I have to get my hands on one of these now…
The original 80s Darda cars were great fun, with enough power to get around great big loops. One of those childhood toys I wish I'd took more care of and kept hold of...
They did still produce a version relatively recently (looks like they're discontinued entirely now?), but the cars were significantly lighter and less powerful, all-plastic where the originals had metal bodies