Snapshot, 1973: Your delivery has arrived, Mr Penske
The International Race of Champions, the brainchild of Roger Penske, has been devised to pit the very finest drivers from a number of different disciplines against each other in identical Porsche 911s, at four events – three at Riverside, and a ‘season’ finale at Daytona. While the entry list is populated by a host of great names such as Emerson Fittipaldi, Denny Hulme, Richard Petty, and Peter Revson, it is the comparatively lesser-known Mark Donohue who will become the first IROC champion after winning three of the four races. Note the colourful cars’ ducktail spoilers.