PORSCHE RACING HISTORYKlaus Drees (D)
1978
19 March 1978 - Mugello 6 Hours - World Championship for Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 29 | Porsche 935 | 930 670 0540 | Gr.5 | Klaus Drees (D)/Wolfgang Kauwertz (D) | Klaus Drees (D) | 16th | 12th | 25th | 133 laps |
22 April 1978 - Dijon 6 Hours - World Championship for Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 12 | Porsche 935 | 930 670 0540 | Gr.5 | Klaus Drees (D)/Wolfgang Kauwertz (D)/Peter Hähnlein (D) | Klaus Drees (D) | 10th | 8th | 15th | 146 laps |
14 May 1978 - Silverstone 6 Hours - World Championship for Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 17 | Porsche 935 | 930 670 0540 | Gr.5 | Mike Franey (GB)/Klaus Drees (D) | Klaus Drees (D) | 14th | 9th | 14th | 183 laps |
28 May 1978 - Nürburgring 1000 km - World Championship for Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 19 | Porsche 935 | 930 670 0540 | Gr.5+2.0 | Klaus Drees (D)/Peter Hähnlein (D) | Klaus Drees (D) | 17th | 11th | 45th | 39 laps |