| 01 | Papis / Pruett | CompUSA Chip Ganassi Racing (USA) | Chip Ganassi | Riley | Mk XI | | Lexus | DP |
| 02 | Morales / Diaz | CompUSA Chip Ganassi Racing (USA) | Chip Ganassi | Riley | Mk XI | | Lexus | DP |
| 04 | Sigal / Zaid | Grease Monkey Racing (USA) | Gene Sigal | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 06 | Hemmingson / Rosenblum | ICY/SL Motorsports (USA) | Steve Lisa | Chevrolet | Corvette | | Chevrolet | GT |
| 09 | Goad / Grégoire | 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 | Rice / Lewis | Southard Motorsports (USA) | Steve Southard | Fabcar | FDSC/03 | | BMW | DP |
| 10 | Taylor / Angelelli | SunTrust Racing (USA) | Wayne Taylor | Riley | Mk XI | | Pontiac | DP |
| 14 | Keen / Friedman | Autometrics Motorsports (USA) | Cory Friedman | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 16 | Collins / Milner | Prototype Technology Group (USA) | Tom Milner | BMW | M3 | E46 | BMW | GT |
| 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 |
| 23 | Espenlaub / Del Vecchio | Horizon Motorsports LLC (USA) | Jim Harrell | Pontiac | GTO | | Pontiac | GT |
| 27 | Theys / Montermini | Doran-Lista Racing (USA) | Kevin Doran | Doran | JE4 | | Lexus | DP |
| 33 | Barbosa / Assentato / Earle | Scuderia Ferrari of Washington (USA) | Allie Ash, Jr. | Maserati | Trofeo Light | | Maserati | GT |
| 34 | Segal / West | Scuderia Ferrari of Washington (USA) | Allie Ash, Jr. | Maserati | Trofeo Light | | Maserati | GT |
| 36 | Levitas / Pobst | TPC Racing (USA) | Michael Levitas | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 37 | Littlechild / *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 | Davis / Hall | The Spark of Georgia Tech (USA) | Larry Huang/Chris Hall | Crawford | DP03 | | Pontiac | DP |
| 41 | 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 | Shanaman / Shanaman | Orison-Planet Earth Motorsports (USA) | Joe Nonnamaker | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 47 | Ward / Baughman | Michael Baughman Racing (USA) | Michael Baughman | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 54 | Fittipaldi / Borcheller | Kodak - Bell Motorsports (USA) | James Bell | Doran | JE4 | | Pontiac | DP |
| 57 | Vance / Stevenson | Stevenson Motorsports/Auto Assets (USA) | John Stevenson | Porsche | 996 GT3-R | | Porsche | GT |
| 58 | Donohue / Law | Red Bull - Brumos Racing (USA) | Bob Snodgrass | Fabcar | FDSC/03 | | Porsche | DP |
| 59 | France / Haywood / *Goodyear | Brumos Racing (USA) | Bob Snodgrass | Fabcar | FDSC/03 | | Porsche | DP |
| 60 | Jeannette / Franchitti | Gunnar Racing (USA) | Bob Snodgrass | Porsche | 996 GT3-RS | | Porsche | GT |
| 65 | Master / Pattee | The Racers Group (USA) | Kevin Buckler | Porsche | 996 GT3 Cup | | Porsche | SGS |
| 66 | Valentine / Gleason / James | The Racers Group (USA) | Kevin Buckler | Porsche | 996 GT3-RS | | Porsche | GT |
| 67 | Nearn / 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) | Cole Scrogham | Porsche | 996 GT3-RS | | Porsche | GT |
| 81 | Wagner / Martini | Rx.com/G&W Motorsports (USA) | Cole Scrogham | Doran | JE4 | | BMW | DP |
| 84 | Mortimer / *McKenzie | Acme Motorsport (USA) | Paul Mortimer | Porsche | 996 GT3-RS | | Porsche | GT |
| 86 | Van Wijk / Stanton | G&W Motorsports (USA) | Cole Scrogham | Porsche | 996 GT3 Cup | I | Porsche | SGS |