PORSCHE RACING HISTORYPorsche 914/6 - Chassis No. 914 043 0593
18 March 1978 - Sebring 12 Hours - World Challenge for Endurance Drivers
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 62 | Porsche 914/6 | 914 043 0593 | GTU | Bill Koll (USA)/David Hamren (USA)/Dennis Sherman (USA) | William J. Koll (USA) | 10th | 3rd | 53rd | 209 laps |
2 April 1978 - Talladega 6 Hours - World Challenge for Endurance Drivers
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 62 | Porsche 914/6 | 914 043 0593 | GTU | Bill Koll (USA)/David Hamren (USA) | William Koll (USA) | 11th | 4th | 32nd | 148 laps |
18 June 1978 - Brainerd 100 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 62 | Porsche 914/6 | 914 043 0593 | GTU | Bill Koll (USA) | William Koll (USA) | 18th | 3rd | 22nd | 29 laps |
4 July 1978 - Daytona 250 Miles Paul Revere - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 62 | Porsche 914/6 | 914 043 0593 | GTU | Bill Koll (USA) | William Koll (USA) | 22nd | 8th | 48th | 57 laps |
4 February 1979 - Daytona 24 Hours - World Championship for Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 62 | Porsche 914/6 | 914 043 0593 | GTU | Bill Koll (USA)/Jim Cook (USA) | Koll Motorsports (USA) | 17th | 7th | 39th | 511 laps - DNF |
17 March 1979 - Sebring 12 Hours - World Challenge for Endurance Drivers
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 62 | Porsche 914/6 | 914 043 0593 | GTU | Bill Koll (USA)/Jim Cook (USA)/Dennis Aase (USA) | Koll Motor Sports (USA) | 22nd | 6th | 20th | 182 laps |
22 April 1979 - Riverside 6 Hours - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 62 | Porsche 914/6 | 914 043 0593 | GTU | Bill Koll (USA)/Bill Bean (USA) | Koll Motor Sports (USA) | 13th | 3rd | 31st | 174 laps |
17 June 1979 - Brainerd 100 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 62 | Porsche 914/6 | 914 043 0593 | GTU | Bill Koll (USA) | Koll Motor Sports (USA) | 22nd | 2nd | 16th | 29 laps |
4 July 1979 - Daytona Paul Revere 250 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 62 | Porsche 914/6 | 914 043 0593 | GTU | Bill Koll (USA)/Jim Cook (USA) | Koll Motor Sports (USA) | 16th | 5th | 31st | 56 laps |
15 July 1979 - Mid-Ohio 250 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 62 | Porsche 914/6 | 914 043 0593 | GTU | Bill Koll (USA)/Jim Cook (USA) | Koll Motor Sports (USA) | 29th | 9th | 24th | 58 laps - DNF |
2 September 1979 - Road America 500 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 62 | Porsche 914/6 | 914 043 0593 | GTU | Bill Koll (USA)/Jim Cook (USA) | Koll Motor Sports (USA) | 13th | 4th | 24th | 112 laps |
3 February 1980 - Daytona 24 Hours - World Championship for Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 62 | Porsche 914/6 | 914 043 0593 | GTU | Bill Koll (USA)/Jim Cook (USA)/Greg LaCava (USA) | William J. Koll (USA) | 5th | 1st | 48th | 632 laps |
27 April 1980 - Riverside 5 Hours - World Challenge for Endurance Drivers
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 45 | Porsche 914/6 | 914 043 0593 | GTU | Ray Ratcliff (USA)/Bill Koll (USA) | R. F. Ratcliff (USA) | 21st | 6th | 49th | 137 laps |
1 February 1981 - Daytona 24 Hours - World Championship for Drivers and Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 45 | Porsche 914/6 | 914 043 0593 | GTU | M. L. Speer (USA)/Dwight Mitchell (USA)/Ray Ratcliff (USA) | Autosport Technology (USA) | 13th | 7th | 58th | 581 laps |
21 March 1981 - Sebring 12 Hours - World Championship for Drivers and Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 45 | Porsche 914/6 | 914 043 0593 | GTU | Dwight Mitchell (USA)/Ray Ratcliff (USA)/Bill Cooper (USA) | Autosport Technology (USA) | 18th | 5th | 32nd | 189 laps - Gearbox |
26 April 1981 - Riverside 6 Hours - World Championship for Drivers and Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 45 | Porsche 914/6 | 914 043 0593 | GTU | Bill Cooper (USA)/Dwight Mitchell (USA)/Ray Ratcliff (USA) | Autosport Technology (USA) | 29th | 8th | 30th | 132 laps |
25 April 1982 - Riverside 6 Hours - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 45 | Porsche 914/6 | 914 043 0593 | GTU | Bobby Hefner (USA)/Bill Cooper (USA)/Jim Luckman (USA) | Garretson Development | 16th | 9th | 34th | 166 laps |
19 March 1983 - Sebring 12 Hours - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 31 | Porsche 914/6 | 914 043 0593 | GTU | Jack Griffin (USA)/John Zouzelka (USA) | Pegasus Racing | 76th | 25th | 86th | 38 laps - Accident |