A.J. Foyt Jr. looks on as his crew works to change the engine on the Sheraton Thompson Special during qualifying for the March 17, 1968 race. Photographer John Isom said Foyt “blew his engine on the second lap of his allotted three-lap qualification” run. “Unbelievably, he managed to install a new engine in time to qualify for the race!” (Photo courtesy of John Isom)