| 01 | Papis / Pruett | CompUSA Chip Ganassi with Felix Sabates (USA) | Chip Ganassi | Riley | Mk XI | | Lexus | DP |
| 02 | Morales / Diaz | CompUSA Chip Ganassi with Felix Sabates (USA) | Chip Ganassi | Riley | Mk XI | | Lexus | DP |
| 04 | Brix / Sigal | Grease Monkey Racing (USA) | Gene Sigal | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 04T | Brix / Sigal | Grease Monkey Racing (USA) | Gene Sigal | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 06 | Lisa / *Jones / *Hemmingson | ICY/SL Motorsports (USA) | Steve Lisa | Chevrolet | Corvette | | Chevrolet | GT |
| 09 | Grégoire / Goad | Spirit of Daytona Racing (USA) | Troy Flis | Crawford | DP03 | | Pontiac | DP |
| 2 | Duno / Wallace | CITGO - Howard - Boss Motorsports (USA) | Rick Howard | Crawford | DP03 | | Pontiac | DP |
| 4 | Forbes-Robinson / Leitzinger | Howard - Boss Motorsports (USA) | Rick Howard | Crawford | DP03 | | Pontiac | DP |
| 6 | Negri / Frisselle | Michael Shank Racing (USA) | Michael Shank | Doran | JE4 | | Lexus | DP |
| 7 | Lewis / Rice | Southard Motorsports (USA) | Steve Southard | Fabcar | FDSC/03 | | BMW | DP |
| 9 | Borkowski / Mears, Jr. | Mears Motorcoach/SpeedSource (USA) | Sylvain Tremblay | Riley | Mk XI | | Pontiac | DP |
| 10 | Taylor / Collard | SunTrust Racing (USA) | Wayne Taylor | Riley | Mk XI | | Pontiac | DP |
| 14 | Friedman / Patch | Autometrics Motorsports (USA) | Cory Friedman | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 21 | Auberlen / Marks | Prototype Technology Group (USA) | Tom Milner | BMW | M3 | E46 | BMW | GT |
| 22 | Said / Hand | Prototype Technology Group (USA) | Tom Milner | BMW | M3 | E46 | BMW | GT |
| 24 | Bambard / Nowicki | Specter Werks/Sports (USA) | Jack Cauley | Chevrolet | Corvette C5 | | Chevrolet | GT |
| 27 | Theys / Leuenberger | Doran Lista Racing (USA) | Kevin Doran | Doran | JE4 | | Lexus | DP |
| 33 | Assentato / Barbosa / Earle | Scuderia Ferrari of Washington (USA) | Allie Ash, Jr. | Maserati | Trofeo Light | | Maserati | GT |
| 36 | Levitas / Dumoulin | TPC Racing (USA) | Michael Levitas | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 37 | Littlechild / Zacharias / *Dumoulin | TPC Racing (USA) | Michael Levitas | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 38 | Bunting / Lally | TPC Racing (USA) | Michael Levitas | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 39 | Hall / Huang | The Spark of Georgia Tech (USA) | Larry Huang/Chris Hall | Crawford | DP03 | | Pontiac | DP |
| 41 | Nonnamaker / *Nonnamaker / *Nonnamaker | Orison-Planet Earth Motorsports (USA) | Joe Nonnamaker | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 42 | Nonnamaker / Nonnamaker / *Nonnamaker | Orison-Planet Earth Motorsports (USA) | Joe Nonnmaker | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 43 | Nonnamaker / Nonnamaker / Nonnamaker | Orison-Planet Earth Motorsports (USA) | Joe Nonnamaker | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 44 | Policastro, Jr. / Policastro / Fitzgerald | Orbit Racing (USA) | Rodger Hawley | Porsche | 996 GT3-RS | | Porsche | GT |
| 46 | Mason / Yeakle | Michael Baughman Racing (USA) | Michael Baughman | Chevrolet | Corvette | Z06 | Chevrolet | SGS |
| 47 | Ward / Baughman | Michael Baughman Racing (USA) | Michael Baughman | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 54 | Barber / Borcheller | Kodak - Bell Motorsports (USA) | James Bell | Doran | JE4 | | Pontiac | DP |
| 57 | Vance / Lewis | Stevenson Motorsports/Auto Assets (USA) | John Stevenson | Porsche | 996 GT3-R | | Porsche | GT |
| 58 | Law / Donohue | Red Bull - Brumos - Goodyear - Kendall (USA) | Bob Snodgrass | Fabcar | FDSC/03 | | Porsche | DP |
| 59 | France / Haywood | Brumos - Goodyear - Kendall (USA) | Bob Snodgrass | Fabcar | FDSC/03 | | Porsche | DP |
| 62 | Halsmer / *Curran | Honda of America Racing Team (USA) | Kyle David Koestner | Acura | NSX | | Acura | GT |
| 66 | Gleason / Valentine / James | The Racers Group (USA) | Kevin Buckler | Porsche | 996 GT3-RS | | Porsche | GT |
| 67 | Halliday / Buckler | The Racers Group (USA) | Kevin Buckler | Porsche | 996 GT3-RS | | Porsche | GT |
| 73 | Tafel / Baldwin | Baldwin-Tafel Racing (USA) | Jack Baldwin/Jim Tafel | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 77 | Greenberg / Pumpelly | G&W Motorsports (USA) | Mark Greenberg | Porsche | 996 GT3-RS | | Porsche | GT |
| 81 | Martini / Wagner | Rx.com/G&W Motorsports (USA) | Cole Scrogham | Doran | JE4 | | BMW | DP |
| 84 | McKenzie / Mortimer | Acme Motorsport (USA) | Paul Mortimer | Porsche | 996 GT3-RS | | Porsche | GT |
| 86 | Van Wijk / Marshall | G&W Motorsports (USA) | Cole Scrogham | Porsche | 996 GT3 Cup | I | Porsche | SGS |