PORSCHE RACING HISTORYWilliam C. Buff (USA)
1956 : Rheinland-Pfalz Preis Nürburgring - 2nd in class
27 May 1956 - Nürburgring 1000 km - World Sports Car Championship
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 47 | Porsche 550 Spyder | 550-0081 | ser.S1.5 | William C. Buff (USA)/Gotfrid Koechert (D) | William C. Buff | DNF |
5 August 1956 - Rheinland-Pfalz Preis Nürburgring - German Sports Car Championship
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 69 | Porsche 550 Spyder | 550-0081 | ser.S1.5 | William C. Buff (USA) | 9th | 2nd | 7 laps |