The quickest vintage Mustang on the planet does not have a carburetor, a camshaft, or an exhaust note. Built from a 1968 fastback by a shop in Austin, Texas, it runs a quarter mile in the nine-second range and holds a top-speed record set over a flying mile. The numbers behind it are strange enough that most people have to read them twice. Read on for what is actually bolted under that sheet metal.