PORSCHE RACING HISTORYLudwig Heimrath, Sr (CDN)
1981
1 February 1981 - Daytona 24 Hours - World Championship for Drivers and Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 07 | Porsche 935 | 930 770 0958 | GTX | Ludwig Heimrath, Sr (CDN)/Ludwig Heimrath, Jr (CDN) | Heimrath Racing (CDN) | 14th | 5th | 17th | 575 laps |
21 March 1981 - Sebring 12 Hours - World Championship for Drivers and Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 07 | Porsche 935 | 930 770 0958 | GTX | Ludwig Heimrath, Sr (CDN)/Ludwig Heimrath, Jr (CDN) | Heimrath Porsche (CDN) | 62nd | 21st | 11th | 57 laps - Accident |
12 July 1981 - Watkins Glen 6 Hours - World Championship for Drivers and Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 7 | Porsche 935 | 930 770 0958 | Gr.5 | Ludwig Heimrath, Sr (CDN)/Ludwig Heimrath, Jr (CDN) | Heimrath Racing (CDN) | DNF | 12th | 64 laps - Drive Shaft |
16 August 1981 - Mosport 6 Hours - World Championship for Drivers and Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 07 | Porsche 924 Carrera GTR | WP0ZZZ93ZBS720005 | GTO | Ludwig Heimrath, Jr (CDN)/Ludwig Heimrath, Sr (CDN) | Heimrath Racing (CDN) | 15th | 4th | 15th | 186 laps |
30 August 1981 - Mid-Ohio 500 km - Non Championship Race
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 07 | Porsche 924 Carrera GTR | WP0ZZZ93ZBS720005 | Gr.4 | Ludwig Heimrath, Sr (CDN)/Ludwig Heimrath, Jr (CDN) | Heimrath Racing (CDN) | 24th | 17th | 22nd | 103 laps - DNF |