Following several podium finishes with the still underpowered two liter Porsche 906 and later models, he won the 1968 24 Hours of Daytona in a 907 as well as the Sebring 12 Hours again, now together with Swiss Jo Siffert.
Logo de varios finais no podio co pouco potente dous litros Porsche 906 e modelos posteriores, gañou as 24 horas de Daytona de 1968 cun 907 así como as 12 horas de Sebring novamente, agora xunto co suízo Jo Siffert.