Somewhere along the way in the race, the 43 lost a cylinder. But even with just seven cylinders, the King went on to beat second place Bobby Allison by seven laps.
In his book Forty Years of Stock Car Racing: Volume 4, Greg Fielden writes:
Petty grabbed the lead with 30 laps to go when leader David Pearson broke a transmission housing. Pearson brought the car to the pits and dismounted. Glen Wood repaired the car and wanted to re-enter the race, but Pearson had already gone to the dressing room. Wood noticed LeeRoy Yarbrough standing by in civilian clothes. "I wanted to put LeeRoy in the car , but NASCAR wouldn't let him drive without a uniform." said Wood. Yarbrough had showered and gotten out of his uniform when Wood noticed him. Pearson got credit for eighth place based on the 470 laps he completed. ~ p. 22Right before the Martinsville race, Petty announced his team was switching from Plymouths to Dodges. For the rest of 1972, Petty raced a Dodge on the faster superspeedways. He continued to run Plymouths on tracks such as the Riverside road course, short tracks, and intermediate tracks such as Trenton and Dover. By 1973, he changed to Dodge for all tracks.
Article courtesy of Jerry Bushmire