PORSCHE RACING HISTORYCraig Siebert (USA)
1981 : Daytona 24 Hours - 2nd overall
1 February 1981 - Daytona 24 Hours - World Championship for Drivers and Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 5 | Porsche 935 K3 | 009 00016 | GTX | Bob Akin (USA)/Craig Siebert (USA)/Derek Bell (GB) | Bob Akin Motor Racing (USA) | 2nd | 2nd | 8th | 695 laps |
21 March 1981 - Sebring 12 Hours - World Championship for Drivers and Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 5 | Porsche 935 K3 | 009 00016 | GTX | Bob Akin (USA)/Derek Bell (GB)/Craig Siebert (USA) | Bob Akin Motor Racing (USA) | 60th | 20th | 8th | 62 laps - Engine |
14 June 1981 - Le Mans 24 Hours - World Championship for Drivers and Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 43 | Porsche 935 K3/80 | 000 00013 | IMSA GTX | Paul Miller (USA)/Craig Siebert (USA)/Bob Akin (USA) | Bob Akin Motor Racing (USA) | DNF | 30th | 320 laps - Short Circuit |
12 July 1981 - Watkins Glen 6 Hours - World Championship for Drivers and Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 43 | Porsche 935 K3/80 | 000 00013 | Gr.5 | Bob Akin (USA)/Craig Siebert (USA)/Vivian Candy (IRL) | Bob Akin Motor Racing, Inc. (USA) | 8th | 7th | 10th | 146 laps |