Lol this was great thanks for doing it. You have to score 200 to unlock No Damage High Impact mode. It's pretty entertaining to send the cars flying but no challenge.
The points are on a timer every half second you get a point and new cars spawn. It gets faster when you have >= 150, more cars and more points while alive. My absolute best is about 250. If you're really struggling you can cheat and edit the config.cfg file in the game folder.
