| 01 | Pruett / Rojas / Montoya / Franchitti | Chip Ganassi with Felix Sabates (USA) | Mike Hull | Riley | Mk XI | | Lexus | DP |
| 02 | Dixon / Wheldon / Duran / Lloyd | Chip Ganassi with Felix Sabates (USA) | Mike Hull | Riley | Mk XI | | Lexus | DP |
| 03 | Carpenter / Foyt / Meira / Andretti / *George | Vision Racing | Larry Curry | Crawford | DP03 | | Porsche | DP |
| 06 | Reese / Nearn / Pilgrim / Bunting | Banner Racing (USA) | Leighton Reese | Pontiac | GXP.R | | Pontiac | GT |
| 07 | Edwards / Collins / Magnussen | Banner Racing | Leighton Reese | Pontiac | GXP.R | | Pontiac | GT |
| 08 | Goldin / Goldin / Meassick / Kennedy | Goldin Brothers Racing | Steve Goldin | Mazda | RX-8 | | Mazda | GT |
| 09 | Cosmo / Camirand / McDowell | Spirit of Daytona Racing | Troy Flis | Fabcar | FDSC/03 | Evo | Porsche | DP |
| 2 | Rockenfeller / McNish / Luhr / *Zogaib | SAMAX | Peter Baron | Riley | Mk XI | | Pontiac | DP |
| 3 | Lewis / Lester / Christopher / Barron | Southard Motorsports | Steve Southard | Riley | Mk XI | | Lexus | DP |
| 6 | Pew / James / Allmendinger / Frisselle | Michael Shank Racing | Michael Shank | Riley | Mk XX | | Ford | DP |
| 7 | Plumb / Wahl / Grégoire / Cullen / Shovlin | Sigalsport | Emmanuel Lupe | Riley | Mk XI | | BMW | DP |
| 9 | Briscoe / Castroneves / Busch | Penske-Taylor Racing | Wayne Taylor/Roger Penske | Riley | Mk XI | | Pontiac | DP |
| 10 | Taylor / Angelelli / Valiante / Taylor | SunTrust Racing | Wayne Taylor | Riley | Mk XI | | Pontiac | DP |
| 11 | Dalziel / Enge / Primat / *Duno | SAMAX | Peter Baron | Riley | Mk XI | | Pontiac | DP |
| 12 | Bell / Kasemets / *Bell / *Dallenbach / *Schramm | RVO Motorsports | Dave Watson | Riley | Mk XI | | Pontiac | DP |
| 14 | Friedman / McGehee / Lazzaro / Kelleners | Autometrics Motorsports | Cory Friedman | Porsche | 997 GT3 Cup | | Porsche | GT |
| 15 | Nastasi / Empringham / Dumoulin / Said | Blackforest Motorsports | Brian Nott | Ford | Mustang | | Ford | GT |
| 16 | Garcia / Bobbi / Babini / Ortelli | Cheever Racing (USA) | Eddie Cheever, Jr. | Coyote | CC/08 | | Pontiac | DP |
| 17 | Zitza / Jensen / Jensen / Taylor | Terra Firma Motorsports | Gary Jensen | Porsche | 997 GT3 Cup | | Porsche | GT |
| 21 | Reindler / Alessi / Prewitt / Trenery / Rice | Matt Connolly Motorsports | Matt Connolly | Pontiac | GTO.R | | Pontiac | GT |
| 22 | de Quesada / Basseng / Swartzbaugh / Pilet | Alegra Motorsports | Carlos de Quesada | Porsche | 997 GT3 Cup | | Porsche | GT |
| 23 | Auberlen / Hand / Long / Wallace | Alex Job Racing | Alex Job | Crawford | DP03 | | Porsche | DP |
| 26 | Jacalone / Jacalone / Michaelian / Michaelian / *Gabel | Gotham Competition | Jerome Jacalone | Porsche | 997 GT3 Cup | | Porsche | GT |
| 27 | O'Connell / Roush / Plumb / Wilson | O'Connell Racing | Kevin O'Connell | Porsche | 997 GT3 Cup | | Porsche | GT |
| 29 | Rosenzweig / Woodman / Gabel / Dumoulin / *Gleason | Alegra Motorsports | Carlos de Quesada | Porsche | 997 GT3 Cup | | Porsche | GT |
| 30 | Dobson / Thorne / Staveley / Stone | Racers Edge Motorsports | Jon Mirachi | Mazda | RX-8 | | Mazda | GT |
| 31 | Ingham / Schultis / Contini / Frost / Konôpka | Matt Connolly Motorsports | Matt Connolly | Chase | CCE-001 | | Pontiac | DP |
| 34 | Willsley / Papadopoulos / Fitzgerald / Mowlem | Orbit | Rodger Hawley | Porsche | 997 GT3 Cup | | Porsche | GT |
| 40 | Foster / Espenlaub / Dempsey / Kapudija / Maxwell | Hyper Sport | Joe Foster | Mazda | RX-8 | | Mazda | GT |
| 42 | Nonnamaker / Sahlen / Nonnamaker / Nonnamaker | Team Sahlen | Mike Thomas | Chevrolet | Corvette | | Chevrolet | GT |
| 43 | Sahlen / Nonnamaker / Nonnamaker / Nonnamaker | Team Sahlen | Mike Thomas | Chevrolet | Corvette | | Chevrolet | GT |
| 44 | Paquette / Nixon / Arnold / Van Zanten, Jr. | Bullet Racing | Steve Pacquette | Porsche | 996 GT3 Cup | I | Porsche | GT |
| 48 | Drummond / Grupp / Mandeville / Spencer / Spencer | Team Spencer Motorsports | Dennis Spencer | Mazda | RX-8 | | Mazda | GT |
| 50 | Farano / Jensen / Cloud / Said / Bradley | Blackforest Motorsports | Brian Nott | Ford | Mustang | | Ford | GT |
| 51 | Newton / Erdos / *Kimber-Smith / *Mayer / *Sherman | Cheever Racing | Eddie Cheever, Jr. | Coyote | CC/08 | | Pontiac | DP |
| 52 | Ragazzi / Min Effiniz / Bertuzzi / Castellano / Machado | Mastercar | Mario Crugnola | Ferrari | F430 | Challenge | Ferrari | GT |
| 56 | Marsh / Montanari / *Biagi / *Monzón / *Venier | Mastercar | Mario Crugnola | Ferrari | F430 | Challenge | Ferrari | GT |
| 57 | Liddell / Davis / Pobst / Jeannette | Stevenson Motorsports | John Stevenson | Pontiac | GXP.R | | Pontiac | GT |
| 58 | Law / Donohue / Rice | Brumos Racing | Michael Colucci | Riley | Mk XI | | Porsche | DP |
| 59 | France / Barbosa / Borcheller / Haywood | Brumos Racing (USA) | Michael Colucci | Riley | Mk XI | | Porsche | DP |
| 60 | Patterson / Negri / Wilson / Rahal | Michael Shank Racing | Michael Shank | Riley | Mk XX | | Ford | DP |
| 61 | Frisselle / Wilkins / Ranger / Braun | AIM Autosport | Ian Willis | Riley | Mk XX | | Ford | DP |
| 62 | Ragginger / Burtin / Baldwin / Tucker / Zabinski | TRG (USA) | Kevin Buckler | Porsche | 997 GT3 Cup | | Porsche | GT |
| 63 | Ende / Maher / *Bourque / *Yarab, Jr. | TRG (USA) | Kevin Buckler | Porsche | 997 GT3 Cup | | Porsche | GT |
| 64 | Lowe / Pace / Van Overbeek / Sugden / Valentine | TRG (USA) | Kevin Buckler | Porsche | 997 GT3 Cup | | Porsche | GT |
| 65 | Oasis / Atherton / Stout / Daskalos / Archer | TRG (USA) | Kevin Buckler | Porsche | 997 GT3 Cup | | Porsche | GT |
| 66 | Miller / Ballou / Lally / Westbrook | TRG (USA) | Kevin Buckler | Porsche | 997 GT3 Cup | | Porsche | GT |
| 67 | Pumpelly / Collard / Sellers / Dumas / George, Jr. | TRG (USA) | Kevin Buckler | Porsche | 997 GT3 Cup | | Porsche | GT |
| 68 | Gomez / Auriemma / Mayes / Schroeder / Milner | TRG (USA) | Kevin Buckler | Porsche | 997 GT3 Cup | | Porsche | GT |
| 69 | Assentato / Segal / Longhi / Pechnik | SpeedSource | Sylvain Tremblay | Mazda | RX-8 | | Mazda | GT |
| 70 | Haskell / Tremblay / Ham / Matos | SpeedSource | Sylvain Tremblay | Mazda | RX-8 | | Mazda | GT |
| 72 | Aschenbach / Lewis, Jr. / Stanton / Papis | Autohaus Motorsports | Nathan McBride | Pontiac | GXP.R | | Pontiac | GT |
| 74 | Skea / Patch / Hamblin / Safina / Murry | Autometrics Motorsports | Chris Mitchum | Porsche | 997 GT3 Cup | | Porsche | GT |
| 75 | Krohn / van de Poele / Gavin | Krohn Racing | David Brown | Riley | Mk XI | | Pontiac | DP |
| 76 | Jönsson / Zonta / Turner | Krohn Racing | David Brown | Riley | Mk XI | | Pontiac | DP |
| 77 | Gidley / Jaeger / Gollin / Gardel | Doran Racing | Kevin Doran | Doran | JE4 | | Ford | DP |
| 80 | Greenberg / Faulkner / Heylen / Arnold | Synergy Racing | Cole Scrogham | Porsche | 997 GT3 Cup | | Porsche | GT |
| 81 | Johnson / Doornbos / Lietz / Huisman | Synergy Racing | Cole Scrogham | Porsche | 997 GT3 Cup | | Porsche | GT |
| 83 | Crews / Walker / Ludwig / McCrackin / Bergmeister | Farnbacher Loles | Gregory Loles | Porsche | 997 GT3 Cup | | Porsche | GT |
| 84 | Bingham / Pickering / Cotter / Pennington | Farnbacher Loles | Gregory Loles | Porsche | 997 GT3 Cup | | Porsche | GT |
| 85 | Kitch / Bentley / Miller / Pallis | Farnbacher Loles | Gregory Loles | Porsche | 997 GT3 Cup | | Porsche | GT |
| 86 | Henzler / Lux / Keen / Maassen / Bergmeister | Farnbacher Loles | Gregory Loles | Porsche | 997 GT3 Cup | | Porsche | GT |
| 87 | Farnbacher / Ehret / Bernhard / Werner | Farnbacher Loles | Gregory Loles | Porsche | 997 GT3 Cup | | Porsche | GT |
| 88 | Stippler / Kaffer / Lacey / Wilkins / Curran | Farnbacher Loles | Gregory Loles | Porsche | 997 GT3 Cup | | Porsche | GT |
| 89 | Drudi / Giammaria / Rosa / Hardt / Petrobelli | Farnbacher Loles | Gregory Loles | Porsche | 997 GT3 Cup | | Porsche | GT |
| 90 | Thornton / Long / Varde / Russell | Automatic Racing | Jep Thornton | BMW | M6 | | BMW | GT |
| 91 | Matthews / Goossens / O'Connell / Hunter-Reay | Bob Stallings/Riley-Matthews | Bill Riley | Riley | Mk XX | | Pontiac | DP |
| 99 | Gurney / Fogarty / Vasser / Johnson | Gainsco/Bob Stallings Racing | Bob Stallings | Riley | Mk XI | | Pontiac | DP |