What car was so dangerous that its own company refused to sell it? The TVR Cerbera Speed 12. Built in the late 1990s, was supposed to be Britain's ultimate supercar. It had a 7.7-liter V12 that produced over 1,000 horsepower and a body so light it was practically a race car for the road. But after testing, TVR's founder Peter Wheeler decided it was too insane to sell. He said, "It's simply too powerful for anyone to handle safely." Only one remains today, a reminder that sometimes engineers can