PORSCHE RACING HISTORYChassis No. 473 29 24107
2 May 1976 - Laguna Seca 100 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 54 | Porsche 914/6 | 473 29 24107 | GTU | Fred Maeder (USA) | Fred Maeder (USA) | 27th | 12th | 41st | 42 laps - DNF |
1 May 1977 - Laguna Seca 100 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 54 | Porsche 914/6 | 473 29 24107 | GTU | Fred Maeder (USA) | 35th | 12th | 39th | 18 laps - DNF |
4 June 1978 - Trans-Am Westwood - Trans-Am
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 23 | Porsche 914/6 | 473 29 24107 | TA-I | Bob Zulkowski (USA) | Metal Craft Racing (USA) | 21st | 14th | 19th | 19 laps - CV Joint |
11 June 1978 - Trans-Am Portland - Trans-Am
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 23 | Porsche 914/6 | 473 29 24107 | TA-I | Bob Zulkowski (USA) | Metal Craft Racing (USA) | 32nd | 21st | 32nd | 5 laps - Engine |
8 October 1978 - Trans-Am Laguna Seca - Trans-Am
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 23 | Porsche 914/6 | 473 29 24107 | TA-I | Bob Zulkowski (USA) | Metal Craft Racing (USA) | 31st | 19th | 24th | 33 laps - Turbo Failure |
17 March 1979 - Sebring 12 Hours - World Challenge for Endurance Drivers
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 25 | Porsche 914/6 | 473 29 24107 | GTU | Bob Zulkowski (USA)/Gerard Raney (USA) | Metal Craft Racing (USA) | 60th | 23rd | 47th | 34 laps - DNF |
22 April 1979 - Riverside 6 Hours - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 25 | Porsche 914/6 | 473 29 24107 | GTU | Bob Zulkowski (USA)/Bernie Storc (USA) | Metal Craft Racing (USA) | 41st | 17th | 54th | 42 laps - DNF |
3 June 1979 - Trans-Am Westwood - Trans-Am
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 23 | Porsche 914/6 | 473 29 24107 | TA-I | Bob Zulkowski (USA) | Metal Craft Racing (USA) | 20th | 13th | 14th | 38 laps - Rear End |
7 July 1979 - Watkins Glen 6 Hours - World Championship for Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 23 | Porsche 914/6 | 473 29 24107 | TA-I | Bob Zulkowski (USA)/Bernie Storc (USA) | Metal Craft Racing (USA) | 33rd | 13th | 33rd | 48 laps - DNF |
21 July 1979 - Trans-Am Road America - Trans-Am
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 23 | Porsche 914/6 | 473 29 24107 | TA-I | Bob Zulkowski (USA) | Metal Craft Racing (USA) | 20th | 12th | 27th | 21 laps |
5 August 1979 - Trans-Am Watkins Glen - Trans-Am
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 23 | Porsche 914/6 | 473 29 24107 | TA-I | Bob Zulkowski (USA) | Metal Craft Racing (USA) | 30th | 23rd | 30th | 2 laps - Clutch |
22 March 1980 - Sebring 12 Hours - World Challenge for Endurance Drivers
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 23 | Porsche 914/6 | 473 29 24107 | GTU | Bob Zulkowski (USA)/Dennis Brisken (USA)/Gary Nylander (USA) | Metalcraft Racing (USA) | 55th | 17th | 70th | 73 laps - DNF |
27 April 1980 - Riverside 5 Hours - World Challenge for Endurance Drivers
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 28 | Porsche 914/6 | 473 29 24107 | GTU | Bob Zulkowski (USA)/Bill Johnson (USA) | Metal Craft Racing (USA) | 39th | 15th | 57th | 67 laps |
5 July 1980 - Watkins Glen 6 Hours - World Championship for Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 23 | Porsche 914/6 | 473 29 24107 | Trans Am | Bob Zulkowski (USA)/Gary Pullyblank (CDN)/Bernie Storc (USA) | Metal Craft Racing (USA) | 26th | 11th | 30th | 74 laps - Electrical |