| 0 | Ongais / Field | Interscope Racing (USA) | Ted Field | Porsche | 935 | /79 | Porsche | GTX |
| 00 | Field / Ongais | Interscope Racing (USA) | Ted Field | Porsche | 935 | /77A | Porsche | GTX |
| 01 | White / Overby | Roehrig Racing (USA) | J. Dana Roehrig | Porsche | 911 | S | Porsche | GTU |
| 02 | Roehrig / Roehrig | Roehrig Racing | | Porsche | 911 | | Porsche | GTU |
| 03 | Almeida / Rodriguez / Romero | Motorcito Racing | | Chevrolet | Corvette | C3 | Chevrolet | GTO |
| 04 | Thompkins / Heinz | Rick Thompkins (USA) | | Chevrolet | Corvette | | Chevrolet | GTO |
| 06 | Wonzer / Van Arsdale | Gary J. Wonzer | | Triumph | GT6 | | Triumph | GTU |
| 07 | Cowart / Miller / McClain | Morrison's | | Porsche | 911 Carrera | RSR | Porsche | GTO |
| 08 | Wolters / Buchler / Northam | Moran Construction (USA) | | Porsche | 911 | S | Porsche | GTU |
| 09 | Haywood / Henn / Gregg | Thunderbird Swap-Shop (USA) | Preston Henn | Porsche | 935 | /77A | Porsche | GTX |
| 2 | Henn / St. James / Guthrie | Thunderbird Swap-Shop (USA) | | Ferrari | 365 GTB/4 | | Ferrari | GTO |
| 3 | Garretson / Belcher / Bondurant | Dick Barbour Racing (USA) | Dick Barbour | Porsche | 935 | | Porsche | GTX |
| 4 | Leuzinger / *Van der Werff | B. R. Racing Team | | De Tomaso | Pantera | | Ford | GTO |
| 5 | Mendez / Redman / Miller | Busch Beer Racing (USA) | Charles Mendez | Porsche | 935 | | Porsche | GTX |
| 6 | Stommelen / Barbour / Mears | Dick Barbour Racing (USA) | Dick Barbour | Porsche | 935 | /77A | Porsche | GTX |
| 7 | Heimrath / *"Jamsal" / *Moran | Heimrath Racing (CDN) | Ludwig Heimrath | Porsche | 935 | | Porsche | GTX |
| 8 | Arutunoff / Marina / Sullivan | Automobiles International (USA) | Anatoly Arutunoff | Lancia | Stratos | HF | Ferrari | GTU |
| 9 | Akin / McFarlin / Woods | Dick Barbour Racing (USA) | | Porsche | 935 | | Porsche | GTX |
| 12 | Smith / Tumbleston / Potter | Ford Smith Racing | | Chevrolet | Camaro | | Chevrolet | GTO |
| 13 | Shaw, Jr. / Ridgely | Hal Shaw Racing (USA) | Hal Shaw | Porsche | 935 | | Porsche | GTX |
| 14 | Garza / McVey / Cross | Precision School of Racing | | Porsche | 911 Carrera | | Porsche | GTO |
| 15 | Gebhardt / *Beilcke | Bavarian Motors | | BMW | 3.5 CSL | | BMW | GTO |
| 16 | Overstreet / Mitchell | Overstreet Racing Ent. (USA) | | Porsche | 914 | /6 | Porsche | GTU |
| 17 | LaGrow / Boyer | Kenneth D. LaGrow | | Chevrolet | Camaro | | Chevrolet | GTX |
| 18 | Paul / Holbert | JLP Racing (USA) | John Paul | Porsche | 935 | JLP-1 | Porsche | GTX |
| 21 | Shafer / *Wood | Oftedahl/Shafer Farms (USA) | Gordon Oftedahl | Chevrolet | Camaro | II | Chevrolet | GTO |
| 22 | Kirill / Wellik / Shafer | Oftedahl Racing | Gordon Oftedahl | Chevrolet | Camaro | | Chevrolet | GTO |
| 23 | Kemp / Nierop / Baird | Kemp Motoracing (USA) | Charlie Kemp | Ford | Mustang | II Cobra | Ford | GTX |
| 25 | Zulkowski / Raney | Metal Craft Racing (USA) | | Porsche | 914 | /6 | Porsche | GTU |
| 27 | Mummery / Sheehy / Sereix | Miami Auto Racing | Ray Mummery | Porsche | 911 | S | Porsche | GTU |
| 28 | Kearns / Moretti | Desperado Racing (USA) | Clif Kearns | Porsche | 935 | | Porsche | GTX |
| 29 | Hagan / Overbagh / Reed | Stratagraph (USA) | | Chevrolet | Monza | | Chevrolet | GTO |
| 31 | Cruz / Lopez / Gonzalez | Hiram Cruz | | Porsche | 911 | | Porsche | GTU |
| 33 | Welter / Aten / Refenning | Peter Welter | Peter Welter | Porsche | 911 | | Porsche | GTU |
| 34 | Drolsom / Greb / Maffucci | Drolsom Racing (USA) | George Drolsom | Porsche | 911 | S | Porsche | GTU |
| 36 | Case / Panaccione | Case Racing | | Porsche | 911 | | Porsche | GTU |
| 37 | Espinosa / Lopez / Cortes | Botero Racing Team (CO) | Luis Botero | Porsche | 911 Carrera | RSR | Porsche | GTO |
| 38 | Fernandez / Ferrer / Soldevilla | Boricua Racing (PR) | | Porsche | 911 Carrera | RSR | Porsche | GTO |
| 39 | Trueman / Higgins / Mead | Barrick Motor Racing | | Porsche | 911 | | Porsche | GTU |
| 40 | Southard / *Roe | Performance Specialists | | Porsche | 914 | /6 | Porsche | GTU |
| 41 | Jones, Jr. / Hollis | Jones Ind. Racing (USA) | Herb Jones, Jr. | Chevrolet | Camaro | II | Chevrolet | GTX |
| 43 | McDill / Frank | Meldeau Tire Stores (USA) | | Chevrolet | Camaro | | Chevrolet | GTX |
| 44 | Van Arsdale / Murry | SUD Porsche Racing | | Porsche | 911 | | Porsche | GTU |
| 46 | DeNarvaez / Naon | Mauricio deNarvaez (CO) | Mauricio DeNarvaez | Porsche | 911 Carrera | RSR | Porsche | GTO |
| 47 | Chitwood / Chitwood | Tim Chitwood (USA) | Tim Chitwood | Chevrolet | Nova | | Chevrolet | GTO |
| 48 | Fillingham / *Canfield / *Chitwood | Fillingham Racing | | Chevrolet | Corvette | | Chevrolet | GTO |
| 50 | Brezinka / Hirsch / Hochreuter | R & H Racing (CDN) | | Porsche | 911 | S | Porsche | GTU |
| 51 | Kirby / Baker / Winters | Personalized Porsche (USA) | Wayne Baker | Porsche | 914 | /4 | VW | GTU |
| 52 | Swanson / Gauthier | Ours & Hours Racing | | Chevrolet | Camaro | | Chevrolet | GTO |
| 53 | Thomas / Moise / Nehl | Guy F. Thomas (USA) | | Chevrolet | Camaro | | Chevrolet | GTX |
| 54 | Garcia / Montalvo / Vadia | Montura Ranch Estates (USA) | Tony Garcia | Porsche | 911 Carrera | RSR | Porsche | GTO |
| 56 | Carter / Edwards / Valentine | Peerless Racing (USA) | Rick Hendrick | Chevrolet | Camaro | II | Chevrolet | GTO |
| 57 | Tremblay / *Lapp | J. F. Tremblay | | Datsun | 240Z | | Datsun | GTU |
| 58 | Febles / Currin | Diego Febles Racing (PR) | Diego Febles | Porsche | 911 Carrera | RSR | Porsche | GTO |
| 60 | Bond / Tilton | E. J. Pruitt & Sons | | Porsche | 911 | S | Porsche | GTU |
| 61 | Bean / *Cosentino / *Ashby | Bill Bean | | Mazda | RX-3 | | Mazda | GTU |
| 62 | Koll / Cook / Aase | Koll Motor Sports (USA) | | Porsche | 914 | /6 | Porsche | GTU |
| 66 | Loving / Small / Noseda | Sunset Racing | | Chevrolet | Camaro | | Chevrolet | GTO |
| 67 | Quintana / *Balaguer / *DeCardenas / *Vazquez | Quintana Racing (USA) | | Porsche | 911 | | Porsche | GTU |
| 68 | Cosentino / Bean / Ashby | Faza Squadra (USA) | Alfred Cosentino | Mazda | RX-3 | | Mazda | GTU |
| 69 | Kroll / Bartling | Bytzek Automotive (CDN) | | Porsche | 911 Carrera | RSR | Porsche | GTO |
| 70 | Bohren / Besmer | Walt Bohren Racing | | Mazda | RX-7 | | Mazda | GTX |
| 71 | Jennings / Beasley | Bruce Jennings (USA) | Bruce Jennings | Porsche | 911 | S | Porsche | GTU |
| 72 | Scott / Honegger | Bill Scott Racing-Z&W (USA) | Bill Scott | Porsche | 911 | | Porsche | GTU |
| 74 | Garcia / Cueto | Raul Garcia (USA) | Raul Garcia | Chevrolet | Camaro | II | Chevrolet | GTO |
| 75 | Ramirez / Villa / Gordillo | Mike Ramirez | | Porsche | 911 | | Porsche | GTU |
| 76 | Williams / Doran | Associated Speed & Performance | | Datsun | 240Z | | Datsun | GTU |
| 77 | Mandeville / Johnson / Downing | Roger T. Mandeville (USA) | Roger Mandeville | Mazda | RX-7 | | Mazda | GTX |
| 78 | Gonzalez / Matienzo | Iggy Gonzalez | | Chevrolet | Camaro | | Chevrolet | GTX |
| 79 | Bergstrom / Frisselle | Sports Ltd. Racing (USA) | Bob Bergstrom | Mazda | RX-7 | | Mazda | GTU |
| 81 | Faul / Jones, Jr. / Lang | Jones Ind. Racing | | Chevrolet | Corvette | | Chevrolet | GTO |
| 85 | Hulen / Coupland / Speakman | John E. Hulen (USA) | John Hulen | Porsche | 914 | /6 | Porsche | GTU |
| 86 | Ross / Tavilla | Team Ross Racing | | Ford | Pinto | | Ford | GTX |
| 87 | Williamson / Miller / Gano | U-Mo Racing | Uiterwyk/Moffitt | Chevrolet | Corvette | | Chevrolet | GTO |
| 88 | Yerger / Orlando / Taylor | Day Enterprise Racing | | Alfa Romeo | Alfetta GTV | | Alfa Romeo | GTU |
| 89 | Romero / Soto | Hector Huerta (YV) | | Porsche | 911 Carrera | RSR | Porsche | GTO |
| 90 | Lee / Kump | Bob's Speed Products | | AMC | AMX | | | GTO |
| 91 | Schramm / Frank | Framm Promotions (USA) | | Porsche | 911 Carrera | RSR | Porsche | GTO |
| 92 | Whittington / Whittington / Minter | Whittington Bros. Racing (USA) | | Porsche | 934 | | Porsche | GTO |
| 93 | Deacon / Riley / Franczak | M. Rochas Porsche (CDN) | | Porsche | 914 | /6 | Porsche | GTU |
| 94 | Whittington / Whittington | Whittington Bros. Racing (USA) | Whittington Brothers | Porsche | 935 | /79 | Porsche | GTX |
| 95 | Bond / Dann | Ozone Industries (USA) | | Chevrolet | Monza | | Chevrolet | GTO |
| 97 | Londono / Garces / Gunn | Ricardo Londono (CO) | | Porsche | 935 | | Porsche | GTX |
| 98 | Van Every / Tisdelle | Van Every Racing (USA) | | Porsche | 911 Carrera | RSR | Porsche | GTO |