As a result of the GT40’s extreme speed, the 1968 season saw racing prototypes limited to an engine capacity of 3.0-litres. This saw the disqualification of, among others, the Ferrari 330P and the Mk IV GT40.
However, a further amendment permitted a maximum engine capacity of 5.0-litres if at least 50 cars had been built to-date.
To take full advantage, one of the first MkI GT40s was resurrected and the engine bored from 4.7-litres to 4.9-litres. With these changes, the GT40 won at Le Mans yet again; claiming the 1968 title – the fourth consecutive win – and placing the Ford GT40 as the victor in the 1968 International Championship for Makes.