Bill met Carroll in a department store one day, and Carroll asked Bill why he drove foreign cars - outraged that an American would buy foreign cars. Bill said no American car was fast enough for the daily drive to work. So Carroll took this as a personal slight, being the builder of the coolest and fastest American car, and had a duplicate made of his own personal customized AC Cobra, just like this one in this February 1968 Road and Track article.
Listen to the Bill Cosby stand up routine on side A of the album, 200 MPH around a tree, no one can tell a story as well. Dual supercharged, dual quad, Shelby 427 side oiler... and Carroll had his mechaincs put it together exactly to his specs, and never allowed any others made that could match it. It held the record for the fastest production car for about 3 decades.
Not exactly a production car, but neither is an Enzo model Ferrari. At the level these guys compete, and build, it's close enough for me. Worth reading and learning.