PORSCHE RACING HISTORYRolf Stommelen (D)
1983 : Monza 1000 km - 3rd overall
10 April 1983 - Monza 1000 km - World Endurance Championship
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 12 | Porsche 956 | 956-105 | C | Rolf Stommelen (D)/Clemens Schickentanz (D)/Hans Heyer (D) | Joest Racing | 3rd | 3rd | 7th | 170 laps |
24 April 1983 - Riverside 6 Hours - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 12 | Porsche 935/81 | JR-002 | GTP | Derek Bell (GB)/Rolf Stommelen (D) | John Fitzpatrick (GB) | 32nd | 10th | 2nd | 94 laps - Fatal Accident |