What did we find out?

Every vehicle we tested had some areas of turbulence on it, shown by some of the streamers lifting up off the vehicle. The vehicle with the most streamers that stayed flat was the Indy car, with 16 out of 25. Next was the stock car (14), and then the boat (that was kind of surprising) with 13 flat streamers. The roadster had the fewest flat streamers, only 8. It was the least aerodynamic. We wondered whether we could add spoilers to make the roadster more aerodynamic. We decided to try that another day. more...