At first blush, this just looks like your typical top-down driving game a la Intellivision's "Auto Racing." What makes this game unique is the world-editor. You can build any track you like an populate it with houses and terrain. Make your own challenging courses and play for time, or create something truly devious and try it out on your friends.
There are tons of options, too--play on dry, wet or icy roads; play with real-life or wonky physics; change the top speeds and accelerations of the vehicles involved.
Bottom line--the best game of its type from the early 80's!