PORSCHE RACING HISTORYPorsche 935/77A - Chassis No. 930 890 0021
16 April 1978 - Road Atlanta 100 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 0 | Porsche 935/77A | 930 890 0021 | GTX | Danny Ongais (USA) | Interscope Racing (USA) | 2nd | 2nd | 11th | 40 laps |
30 July 1978 - Sears Point 100 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 0 | Porsche 935/77A | 930 890 0021 | GTX | Ted Field (USA) | Interscope Racing (USA) | 5th | 5th | 9th | 39 laps |
4 September 1978 - Road Atlanta 100 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 0 | Porsche 935/77A | 930 890 0021 | GTX | Ted Field (USA) | Interscope Racing (USA) | 5th | 5th | 14th | 39 laps |
26 November 1978 - Daytona Finale 250 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 0 | Porsche 935/77A | 930 890 0021 | GTX | Ted Field (USA) | Interscope Racing (USA) | 6th | 6th | 7th | 62 laps |
4 February 1979 - Daytona 24 Hours - World Championship for Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 00 | Porsche 935/77A | 930 890 0021 | GTX | Preston Henn (USA)/Ted Field (USA)/Danny Ongais (USA) | Interscope Racing (USA) | 61st | 19th | 11th | 29 laps - Accident |
17 March 1979 - Sebring 12 Hours - World Challenge for Endurance Drivers
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935/77A | 930 890 0021 | GTX | Hurley Haywood (USA)/Preston Henn (USA)/Peter Gregg (USA) | Thunderbird Swap-Shop (USA) | 26th | 9th | 2nd | 157 laps - Engine |
8 April 1979 - Road Atlanta 100 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935/77A | 930 890 0021 | GTX | Preston Henn (USA) | Thunderbird Swap Shops (USA) | 19th | 10th | 11th | 33 laps |
22 April 1979 - Riverside 6 Hours - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935/77A | 930 890 0021 | GTX | Bob Bondurant (USA)/Preston Henn (USA) | Thunderbird Swap Shop (USA) | 35th | 12th | 8th | 99 laps - DNF |
29 April 1979 - Laguna Seca 100 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935/77A | 930 890 0021 | GTX | Preston Henn (USA) | Thunderbird Swap Shop (USA) | 7th | 6th | 13th | 49 laps |
13 May 1979 - Hallett 100 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935/77A | 930 890 0021 | GTX | Preston Henn (USA) | Thunderbird Swap Shop (USA) | 7th | 7th | 11th | 53 laps |
28 May 1979 - Lime Rock 100 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935/77A | 930 890 0021 | GTX | Preston Henn (USA) | Thunderbird Swap Shop (USA) | 11th | 7th | 11th | 59 laps |
17 June 1979 - Brainerd 100 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935/77A | 930 890 0021 | GTX | Preston Henn (USA) | Thunderbird Swap Shop (USA) | 8th | 8th | 43rd | 32 laps |
7 July 1979 - Watkins Glen 6 Hours - World Championship for Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935/77A | 930 890 0021 | Gr.5 | Rick Mears (USA)/Preston Henn (USA)/Peter Gregg (USA) | Bayside Disposal Racing (USA) | 42nd | 5th | 7 laps - Fire |
15 July 1979 - Mid-Ohio 250 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935/77A | 930 890 0021 | GTX | Preston Henn (USA)/John O'Steen (USA) | Michelob Light (USA) | 37th | 10th | 18th | 28 laps - DNF |
5 August 1979 - Trans-Am Watkins Glen - Trans-Am
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935/77A | 930 890 0021 | TA-II | Preston Henn (USA) | Michelob (USA) | 11th | 6th | 5th | 27 laps |
23 September 1979 - Road Atlanta 100 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935/77A | 930 890 0021 | GTX | Preston Henn (USA) | Michelob Light (USA) | 11th | 11th | 16th | 38 laps |
25 November 1979 - Daytona Finale 250 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935/77A | 930 890 0021 | GTX | Preston Henn (USA) | 5th | 5th | 8th | 47 laps |
3 February 1980 - Daytona 24 Hours - World Championship for Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935/77A | 930 890 0021 | GTX | John Paul Sr. (USA)/Al Holbert (USA) | Thunderbird Swap Shop (USA) | 2nd | 2nd | 13th | 682 laps |
22 March 1980 - Sebring 12 Hours - World Challenge for Endurance Drivers
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935 K3 | 930 890 0021 | GTX | John Paul Sr. (USA)/Preston Henn (USA)/Al Holbert (USA) | Thunderbird Swap Shop (USA) | 4th | 4th | 11th | 239 laps |
13 April 1980 - Road Atlanta 100 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 9 | Porsche 935 K3 | 930 890 0021 | GTX | Preston Henn (USA) | Preston Henn (USA) | 24th | 13th | 14th | 16 laps - DNF |
27 April 1980 - Riverside 5 Hours - World Challenge for Endurance Drivers
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935 K3 | 930 890 0021 | GTX | John Paul Sr. (USA)/Preston Henn (USA) | John Paul Racing (USA) | 57th | 19th | 9th | 19 laps - Blown Engine |
4 May 1980 - Laguna Seca 100 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935 K3 | 930 890 0021 | GTX | John Paul Sr. (USA) | Preston Henn (USA) | 3rd | 3rd | 4th | 52 laps |
26 May 1980 - Lime Rock 1.5 Hours - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935 K3 | 930 890 0021 | GTX | John Paul Sr. (USA)/John Paul, Jr. (USA) | Preston Henn (USA) | 1st | 1st | 5th | 92 laps |
17 August 1980 - Mosport 6 Hours - World Championship for Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 9 | Porsche 935 K3 | 930 890 0021 | GTX | Dale Whittington (USA)/Preston Henn (USA) | Thunderbird Racing (USA) | 9th | 8th | 12th | 219 laps - Spin |
31 August 1980 - Road America 500 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935 K3 | 930 890 0021 | GTX | Dale Whittington (USA)/Preston Henn (USA) | Preston Henn (USA) | 4th | 4th | 6th | 121 laps |
21 September 1980 - Road Atlanta 50 Miles - Heat 1 - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935 K3 | 930 890 0021 | GTX | John Paul, Jr. (USA) | Preston Henn (USA) | 4th | 4th | 3rd | 20 laps |
21 September 1980 - Road Atlanta 50 Miles - Heat 2 - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935 K3 | 930 890 0021 | GTX | John Paul, Jr. (USA) | Preston Henn (USA) | 5th | 5th | 3rd | 13 laps |
30 November 1980 - Daytona Finale 250 Miles - IMSA - International Motor Sport Association
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 9 | Porsche 935 K3 | 930 890 0021 | GTX | Preston Henn (USA) | Preston Henn (USA) | 57th | 14th | 6th | 11 laps - DNF |
1 February 1981 - Daytona 24 Hours - World Championship for Drivers and Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935 K3 | 930 890 0021 | GTX | Preston Henn (USA)/Bob Bondurant (USA) | Thunderbird Swap Shops (USA) | 64th | 23rd | 15th | 30 laps - Engine |
21 March 1981 - Sebring 12 Hours - World Championship for Drivers and Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935 K3 | 930 890 0021 | GTX | Preston Henn (USA)/John Gunn (USA)/Gary Belcher (USA) | T-Bird Swap Shop (USA) | 48th | 15th | 18th | 107 laps - DNF |
26 April 1981 - Riverside 6 Hours - World Championship for Drivers and Makes
| No. | Car | # | Class | Drivers | Entrant | Pos | Class | Grid | Notes |
| 09 | Porsche 935 K3 | 930 890 0021 | GTX | Gary Belcher (USA)/Preston Henn (USA)/Marty Hinze (USA) | Preston Henn (USA) | 58th | 20th | 15th | 5 laps - DNF |