| 5.1.1991 | Daytona Test | 16 | #148?? | | Dyson Racing | 2nd |
| 5.1.1991 | Daytona Test | 21 | | | | 10th |
| 3.2.1991 | 24 h Daytona | 0 | #175 | Unser, Jr. / Unser / Unser / Unser | Jochen Dauer Racing | 35th |
| 3.2.1991 | 24 h Daytona | 00 | #172 | Andretti / Andretti / Andretti | Jochen Dauer Racing | 5th |
| 3.2.1991 | 24 h Daytona | 08 | #141 | Andretti / Andretti / Unser, Jr. / Unser | Dauer Racing | DNA |
| 3.2.1991 | 24 h Daytona | 6 | #145 | Wollek / Schneider / Barilla / Sigala | Joest Racing | 31st |
| 3.2.1991 | 24 h Daytona | 7 | #129 | Jelinski / Pescarolo / Haywood / Wollek / "Winter" | Joest Racing | 1st |
| 3.2.1991 | 24 h Daytona | 10 | #F01 (HR3F) | Cord / Hotchkis / Adams / Dyson | Wynn's | 3rd |
| 3.2.1991 | 24 h Daytona | 16 | #148?? | Weaver / Paul, Jr. / Needell | Dyson Racing | 22nd |
| 3.2.1991 | 24 h Daytona | 17 | #177 | Larrauri / Sigala / Brun / Pareja / Purner | Brun Motorsports | DNA |
| 3.2.1991 | 24 h Daytona | 21 | #C06 | Herzog / Stuck / Paul, Jr. / Haywood / Pareja / Sigala / Larrauri | Alucraft | DNA |
| 3.3.1991 | 2 h West Palm Beach | 6 | #142=>011 | Wollek / Schneider | Joest Racing | 18th |
| 3.3.1991 | 2 h West Palm Beach | 7 | #145 | "Winter" / Sigala / Wollek | Joest Racing | 7th |
| 3.3.1991 | 2 h West Palm Beach | 10T | | Jim Adams | Hotchkis Racing | T-car |
| 3.3.1991 | 2 h West Palm Beach | 30 | #001GS | Moretti / Coppelli | Momo/Gebhardt Racing | 17th |
| 10.3.1991 | 500 km Fuji | 2 | #167 | Takahashi / Dickens | Team Taisan Klepper | 5th |
| 10.3.1991 | 500 km Fuji | 3 | #164 | Hoy / Huysman | Team Taisan Klepper | 10th |
| 10.3.1991 | 500 km Fuji | 7 | #168 | Needell / Reid | The Alpha Racing | 8th |
| 10.3.1991 | 500 km Fuji | 92 | #146 | Weaver / Haywood | Team Schuppan | 13th |
| 10.3.1991 | 500 km Fuji | 100 | #106B | Fouché / Andskar | Nisseki Racing Team | 7th |
| 16.3.1991 | 12 h Sebring | 6 | #145 | Wollek / Schneider / Sigala | Joest Porsche Racing | 3rd |
| 16.3.1991 | 12 h Sebring | 7 | #129 | Jelinski / Pescarolo / "Winter" | Joest Porsche Racing | 4th |
| 16.3.1991 | 12 h Sebring | 16 | #148?? | Dyson / Weaver / Paul, Jr. | Dyson Racing | DNA |
| 16.3.1991 | 12 h Sebring | 21 | #C06 | Herzog / Haywood | Alucraft | 42nd |
| 16.3.1991 | 12 h Sebring | 24 | #DR1 | Weaver / Paul, Jr. | Shapiro Motorsports | 25th |
| 16.3.1991 | 12 h Sebring | 30 | #001GS | Moretti / Mundas / Dickens | Momo/Gebhardt Racing | 10th |
| 7.4.1991 | 2 h Miami | 6 | #142=>011 | Schneider / Wollek | Joest Porsche Racing | DNS |
| 7.4.1991 | 2 h Miami | 7 | #145 | Bernd Schneider | Joest Porsche Racing | 6th |
| 7.4.1991 | 2 h Miami | 16 | #148?? | James Weaver | Dyson Racing | 4th |
| 7.4.1991 | 2 h Miami | 30 | #001GS | Moretti / Bell | Momo/Gebhardt | 7th |
| 14.4.1991 | Interserie Hockenheim | 5 | #901 | Otto Altenbach | Obermaier Racing | 3rd |
| 14.4.1991 | Interserie Hockenheim | 7 | #129 | "John Winter" | Joest Porsche Racing | 2nd |
| 14.4.1991 | Interserie Hockenheim | 8 | #145 | Bernd Schneider | Joest Porsche Racing | 1st |
| 14.4.1991 | 430 km Suzuka | 11 | #CK6/05-2 | Reuter / Toivonen | Porsche Kremer Racing | 3rd |
| 14.4.1991 | 430 km Suzuka | 12 | #166 | Fouché / Andskar | Courage Competition (Trust) | 5th |
| 14.4.1991 | 430 km Suzuka | 13 | #106B | Barilla / Elgh | Courage Competition (Nisseki Racing Team) | 8th |
| 14.4.1991 | 430 km Suzuka | 14 | #157 | Cohen-Olivar / Salamin | Team Salamin Primagaz | 9th |
| 14.4.1991 | 430 km Suzuka | 16 | #160 | Larrauri | Repsol Brun Motorsport | DQ |
| 14.4.1991 | 430 km Suzuka | 17 | #008BM | Sigala / Pareja | Repsol Brun Motorsport | 7th |
| 14.4.1991 | 430 km Suzuka | 19 | | Wilson / Lee-Davey | Team Davey | DNA |
| 14.4.1991 | 430 km Suzuka | 20 | | Gabbiani / Langes | Team Davey | DNA |
| 14.4.1991 | Interserie Hockenheim | 30 | #001GS | Günter Gebhardt | Gebhardt Racing | 4th |
| 28.4.1991 | 300 km Road Atlanta | 6 | #142=>011 | Bob Wollek | Joest Porsche Racing | DNA |
| 28.4.1991 | 300 km Road Atlanta | 7 | #016 | "Winter" / Schneider | Joest Porsche Racing | 8th |
| 28.4.1991 | 300 km Road Atlanta | 16 | #148?? | Weaver | Dyson Racing | 6th |
| 28.4.1991 | 300 km Road Atlanta | 30 | #145 | Moretti / Bell | Momo | 5th |
| 5.5.1991 | 1000 km Fuji | 2 | #167 | Takahashi / Dickens / Hoy | Team Taisan Klepper | DNF |
| 5.5.1991 | 1000 km Fuji | 2T | | Takahashi / Dickens / Hoy | Team Taisan Klepper | T-car |
| 5.5.1991 | 1000 km Fuji | 7 | #168 | Needell / Reid | The Alpha Racing | 7th |
| 5.5.1991 | 430 km Monza | 11 | #CK6/05-2 | Reuter / Toivonen | Porsche-Kremer-Racing | 5th |
| 5.5.1991 | 430 km Monza | 14 | #157 | Cohen-Olivar / Salamin | Team Salamin Primagaz | DNF |
| 5.5.1991 | 430 km Monza | 16 | #160 | Larrauri / Sigala | Repsol Brun Motorsport | 6th |
| 5.5.1991 | 430 km Monza | 17 | #008BM | Pareja / Brun | Repsol Brun Motorsport | DNF |
| 5.5.1991 | 430 km Monza | 19 | | Tim Lee-Davey | Team Davey | DNA |
| 5.5.1991 | 430 km Monza | 20 | | | Team Davey | DNA |
| 5.5.1991 | 430 km Monza | 21 | #CK6/04=>001K | Johansson / Konrad | Konrad-Motorsport | DNF |
| 5.5.1991 | 1000 km Fuji | 92 | #146 | Weaver / Haywood | Team Schuppan | DNA |
| 5.5.1991 | 1000 km Fuji | 100 | #106B | Fouché / Andskar | Nisseki Racing Team | 4th |
| 12.5.1991 | Interserie Nürburgring Supersprint | 1 | | Manuel Reuter | Porsche Kremer Racing | 2nd |
| 12.5.1991 | Interserie Nürburgring Supersprint | 4 | #155 | Jürgen Oppermann | Obermaier Racing | DNS |
| 12.5.1991 | Interserie Nürburgring Supersprint | 5 | #901? | Jürgen Oppermann | Obermaier Racing | DNS |
| 12.5.1991 | Interserie Nürburgring Supersprint | 5 | #901 | Otto Altenbach | Obermaier Racing | 7th |
| 12.5.1991 | Interserie Nürburgring Supersprint | 6 | #910 | Heinz-Jörgen Dahmen | Heinz-Jorgen Dahmen | 6th |
| 12.5.1991 | Interserie Nürburgring Supersprint | 7 | #142=>011 | "John Winter" | Joest Porsche Racing | 3rd |
| 12.5.1991 | Interserie Nürburgring Supersprint | 8 | #145 | Bernd Schneider | Joest Porsche Racing | 1st |
| 12.5.1991 | Interserie Nürburgring Supersprint | 21 | #CK6/04=>001K | Franz Konrad | Alucraft Racing | 4th |
| 19.5.1991 | 430 km Silverstone | 11 | #CK6/05-2 | Reuter / Toivonen | Porsche Kremer Racing | 8th |
| 19.5.1991 | 430 km Silverstone | 11T | #CK6/06 or 07 | Manuel Reuter | Porsche Kremer Racing | T-car |
| 19.5.1991 | 430 km Silverstone | 14 | #157 | Salamin / Cohen-Olivar | Team Salamin Primagaz | NC |
| 19.5.1991 | 430 km Silverstone | 16 | #160 | Larrauri / Pareja | Repsol Brun Motorsport | 7th |
| 19.5.1991 | 430 km Silverstone | 17 | #008BM | Sigala / Brun | Repsol Brun Motorsport | 10th |
| 19.5.1991 | 430 km Silverstone | 21 | #CK6/04=>001K | Konrad / Needell | Konrad Motorsport | DNF |
| 19.5.1991 | 430 km Silverstone | 59 | #TS02C | Palmer / Elgh | Team Salamin Primagaz (Team Schuppan) | DNF |
| 26.5.1991 | Interserie Zeltweg | 1 | | Manuel Reuter | Porsche Kremer Racing | 3rd |
| 26.5.1991 | Interserie Zeltweg | 4 | #155 | Jürgen Oppermann | Obermaier Racing | 6th |
| 26.5.1991 | Interserie Zeltweg | 5 | #901 | Otto Altenbach | Obermaier Racing | DNF |
| 26.5.1991 | Interserie Zeltweg | 6 | #910 | Heinz-Jörgen Dahmen | Heinz-Jürgen Dahmen | DNF |
| 26.5.1991 | Interserie Zeltweg | 7 | #142=>011 | "John Winter" | Joest Porsche Racing | 2nd |
| 26.5.1991 | Interserie Zeltweg | 8 | #145 | Bernd Schneider | Joest Porsche Racing | 1st |
| 26.5.1991 | 2 h Lime Rock | 16 | #148?? | Dyson / Weaver | Dyson Racing | 17th |
| 26.5.1991 | Interserie Zeltweg | 18 | #CK6/04=>001K | Franz Konrad | Konrad Motorsport | 4th |
| 26.5.1991 | Interserie Zeltweg | 111 | | Jürgen Barth | Porsche Kremer Racing | DNS |
| 2.6.1991 | 300 km Mid-Ohio | 7 | #145 | "Winter" / Schneider | Joest Porsche Racing | 20th |
| 2.6.1991 | 300 km Mid-Ohio | 16 | #148?? | Weaver | Dyson Racing | 8th |
| 23.6.1991 | 24 h Le Mans | 46 | #CK6/09 | Needell / Lopez / Foitek | Porsche Kremer Racing | DNF |
| 23.6.1991 | 24 h Le Mans | 51 | #901 | Altenbach / Yver / Lässig | Team Salamin Primagaz (Obermaier Racing) | DNF |