268.432 miles per hour (432 kilometers per hour): V-16 Auto Union
Here's where the reality-show-style shockers come in, right at the end, when you least expect it. (Except that if you've seen enough of those shows, you know that there's always a twist in the last two episodes, so maybe it's actually when you most expect it.)
The fastest times on the German autobahn weren't set yesterday, or a year ago, or even a decade ago. They were set in 1938. On the same day. By Mercedes Benz and Auto Union (which would eventually become Audi).
Bernd Rosemeyer drove an Auto Union streamliner that had a mid-mounted V-16 engine, two superchargers and an estimated 400 horsepower -- not too shabby even today. It was designed by Ferdinand Porsche. What the streamliner didn't have, unfortunately, was enough downforce to keep it planted on the road at high speed. Rosemeyer managed to hit 268.432 miles an hour (432 kilometers per hour) when word came in that the Mercedes-Benz driver had managed a faster speed.
The shockers don't stop there, though. Rosemeyer headed out again, and on that run, tragedy struck. He lost control of his car in crosswinds and was killed.