Daytona, January 1971. It's the second round of the International Championship of Makes - the World Endurance Championship in today's terminology - and Porsche starts as favourite for the 24 Hours.
The German manufacturer has won all but one of the previous year's rounds, topped the season-opening Buenos Aires 1000Km earlier in the month, and John Wyer's crack Gulf JW Automotive team of two 4.9-litre 917Ks has no factory opposition, just an eclectic mix of privateer Ferraris. But among the assorted 512Ss and new, squarer 512M models is an immaculate blue machine that's not been seen before.
Roger Penske's team is well-known in American racing circles but has rarely taken on the Europeans, even though it won Daytona two years ago with a Lola T70 in a remarkable race of attrition. Its Ferrari is rather different to the others.