The International Race Of Champions completed its inaugural season 45 years ago in February of 1974 where Mark Donohue claimed the first crown in the all-star series created by Roger Penske, Les Richter, and Mike Phelps. Using production-based Porsche Carrera RSRs, the modern greats from Formula 1, IndyCar, and NASCAR came together at the Riverside road course in California and the famed Daytona circuit in Florida for four rounds to determined the best driver in a group containing A.J. Foyt, Emerson Fittipaldi, Richard Petty, and other legends of the sport.

With help from Penske to open our podcast, followed by all manner of wild tales from three-time Indy 500 winner Bobby Unser, who placed third in 1974 while hating the Porsches, and returned to win the IROC championship in 1975 after a switch to Chevy Camaros was made, we have a fun look back at the origins of a classic series in a special edition of the Marshall Pruett Podcast.

And just wait until Uncle Bobby starts talking about cheating…

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