| 0 | Field / Ongais / Haywood | Interscope Racing (USA) | Ted Field | Porsche | 935 | /79 | Porsche | GTX | +2000/Gr.5 |
| 00 | Henn / *Field / *Ongais | Interscope Racing (USA) | Ted Field | Porsche | 935 | /77A | Porsche | GTX | |
| 01 | White / Roehrig / Hamilton | D. R. Racing (USA) | J. Dana Roehrig | Porsche | 911 | S | Porsche | GTU | |
| 03 | Calderari / Pallavicini / Vanoli | Lubrifilm Racing (CH) | Angelo Pallavicini | Porsche | 934 | | Porsche | GTO | |
| 06 | Levenson / Baker / Hester | Al Levenson (USA) | | Chevrolet | Corvette | C2 | Chevrolet | GTO | |
| 07 | Cowart / McClain / Miller | Budweiser Racing | | Porsche | 911 Carrera | RSR | Porsche | GTO | |
| 08 | Wolters / Northam / Weiss | Southern Racing Ent. (USA) | | Porsche | 911 | S | Porsche | GTU | |
| 1 | Wollek / Ickx / Gregg | Gelo Racing Team (D) | Georg Loos | Porsche | 935 | /77A | Porsche | GTX | |
| 2 | Schurti / Fitzpatrick / Wollek | Gelo Racing Team (D) | Georg Loos | Porsche | 935 | /77A | Porsche | GTX | +2000/Gr.5 |
| 3 | Finotto / Facetti / Moretti | Jolly Club - Sportwagen Racing Team (I) | Carlo Noce | Porsche | 935 | | Porsche | GTX | |
| 4 | Jöst / Stommelen / Merl | LM Joest Porsche (D) | | Porsche | 935 | /77A | Porsche | GTX | +2000/Gr.5 |
| 5 | Mendez / Rutherford / Miller | Budweiser Racing (USA) | Charles Mendez | Porsche | 935 | | Porsche | GTX | |
| 6 | Barbour / Redman / Newman | Dick Barbour Racing (USA) | Dick Barbour | Porsche | 935 | /77A | Porsche | GTX | |
| 7 | Katayama / Terada / Yorino | Mazda Technical Center | | Mazda | RX-7 | | Mazda | GTU | |
| 8 | Arutunoff / Marina / Sullivan | Automobiles International Inc. (USA) | Anatoly Arutunoff | Lancia | Stratos | HF | Ferrari | GTU | |
| 9 | Akin / McFarlin / Woods | Dick Barbour Racing (USA) | | Porsche | 935 | | Porsche | GTX | |
| 11 | Canepa / Mears / Shelton | Bruce Canepa (USA) | Bruce Canepa | Porsche | 935 | | Porsche | GTX | +2000/Gr.5 |
| 12 | Wellik / Bagley / Chamberlain / *Wood | Oftedahl Racing (USA) | Gordon Oftedahl | Chevrolet | Camaro | | Chevrolet | GTO | |
| 13 | Shaw, Jr. / Spalding / Ridgely | Hal Shaw Racing (USA) | Hal Shaw | Porsche | 935 | | Porsche | GTX | |
| 14 | Griswold / *Earle / *Knoop | Bavarian Motors International | | BMW | 3.0 CSL | | BMW | GTX | |
| 15 | Gebhardt / Grinbold | Bavarian Motors International (USA) | Alf Gebhardt | BMW | 3.5 CSL | | BMW | GTO | |
| 17 | Mederer / Sherman / Kline | Racing Beat | | Mazda | RX-7 | | Mazda | GTU | |
| 18 | Paul / *Holbert / *Keyser | JLP Racing (USA) | John Paul | Porsche | 935 | JLP-1 | Porsche | GTX | |
| 21 | Wood / Bagley / Shafer | Oftedahl Racing (USA) | Gordon Oftedahl | Chevrolet | Camaro | II | Chevrolet | GTO | |
| 23 | Kemp / Baird / Nierop | Charlie Kemp (USA) | Charlie Kemp | Ford | Mustang | II Cobra | Ford | GTX | |
| 24 | Shaw / Yenko / Thompson | Graham Shaw | | Chevrolet | Monza | | Chevrolet | GTX | |
| 27 | Mummery / Sheehy / Sereix | Miami Auto Racing | Ray Mummery | Porsche | 911 | S | Porsche | GTU | |
| 29 | Hagan / Overbagh / Reed | Stratagraph Inc. (USA) | | Chevrolet | Monza | | Chevrolet | GTO | |
| 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 (CO) | Luis Botero | Porsche | 911 Carrera | RSR | Porsche | GTO | |
| 38 | Fernandez / Soldevilla / Ferrer | Boricua Racing (PR) | | Porsche | 911 Carrera | RSR | Porsche | GTO | |
| 40 | Southard / Koch / Roe | Performance Specialists | | Porsche | 914 | /6 | Porsche | GTU | |
| 42 | Ashby / Bean / Beasley | Bullwinkele Racing, Inc. (USA) | | Porsche | 911 | S | Porsche | GTU | |
| 43 | McDill / Behr | Meldeau Tire Co. | | Chevrolet | Camaro | | Chevrolet | GTX | |
| 46 | DeNarvaez / Naon / DeNarvaez | Mauricio De Narvaez (CO) | Mauricio DeNarvaez | Porsche | 911 Carrera | RSR | Porsche | GTO | |
| 48 | Leary / *Mollett / *Cook | Frank L. Leary, III (USA) | | Datsun | 240Z | | Datsun | GTU | |
| 51 | Kirby / Hotchkis / Meister | Casablanca Fan Co. | John Hotchkis | Porsche | 911 Carrera | RSR | Porsche | GTO | |
| 53 | Thomas / Moise / Nehl | Guy 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 | John 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 | Cosentino / Starita / Akaike | Faza Squadra (USA) | Alfred Cosentino | Mazda | RX-3 | | Mazda | GTU | |
| 62 | Koll / Cook | Koll Motorsports (USA) | | Porsche | 914 | /6 | Porsche | GTU | |
| 63 | Cosentino / Fisher | Faza Squadra | | Mazda | RX-3 | | Mazda | GTU | |
| 64 | Canada / Boykin / Ciccone | Lenton B. McGill (USA) | C. C. Canada | Chevrolet | Camaro | I | Chevrolet | GTO | |
| 65 | Morton / Adamowicz | Modena Sports Cars | | Ferrari | 365 GTB/4 | | Ferrari | GTO | +2000/Gr.5 |
| 66 | Andruet / Dini / Ballot-Léna | JMS Racing-Pozzi | | Ferrari | 512 BB | /LM | Ferrari | GTX | +2000/Gr.5 |
| 67 | Ballot-Léna / Leclère / Andruet | JMS Racing-Pozzi | | Ferrari | 512 BB | /LM | Ferrari | GTX | +2000/Gr.5 |
| 68 | Tullius / Delaunay / Bedard | N.A.R.T. (USA) | | Ferrari | 512 BB | /LM | Ferrari | GTX | +2000/Gr.5 |
| 69 | Bytzek / Bartling / Heimrath | Bytzek Automotive (CDN) | | Porsche | 911 Carrera | RSR | Porsche | GTO | |
| 71 | Scott / Hutchins / Honegger | Bill Scott Racing (USA) | Bill Scott | Porsche | 911 | | Porsche | GTU | |
| 73 | Howey / *Koch / *Wolf | Howey Farms (USA) | | Chevrolet | Camaro | II | Chevrolet | GTX | |
| 75 | Ramirez / Villa / Gordillo | Mike Ramirez | | Porsche | 911 | | Porsche | GTU | |
| 77 | Bohren / Johnson / Mandeville | Mazda Technical Center | | Mazda | RX-7 | | Mazda | GTU | |
| 78 | Williams / Doran / Upchurch | Associated Speed & Performance | | Datsun | 240Z | | Datsun | GTU | |
| 79 | Bergstrom / *Frisselle | Sports Ltd. Racing (USA) | Bob Bergstrom | Mazda | RX-7 | | Mazda | GTU | |
| 80 | Adams / Frey / Spoerl | Herb Adams (USA) | Herb Adams | Pontiac | Firebird | | Pontiac | GTO | |
| 81 | Soto / Romero / Notz | Performance Export (YV) | | Porsche | 911 Carrera | RSR | Porsche | GTO | |
| 89 | Hamilton / Hoskins / Forrest | Hamilton House Racing (USA) | | Porsche | 911 | S | Porsche | GTU | |
| 90 | Kump / Lee / Miller | Bob's Speed Products (USA) | | AMC | AMX | | | GTO | |
| 93 | Whittington / Whittington / Henn | Whittington Bros. Racing (USA) | | Porsche | 934 | | Porsche | GTO | |
| 94 | Whittington / Whittington / Barth | Whittington Bros. Racing (USA) | Whittington Brothers | Porsche | 935 | /79 | Porsche | GTX | +2000/Gr.5 |
| 95 | Bond / Dann | Stephen E. Bond (USA) | | Chevrolet | Monza | | Chevrolet | GTO | |
| 96 | Wonzer / *Whitaker / *Van Arsdale / *Hughes | Gary Wonzer | | Triumph | GT6 | | Triumph | GTU | |
| 98 | Van Every / Tisdelle / Overby | Van Every Racing (USA) | | Porsche | 911 Carrera | RSR | Porsche | GTO | |
| T | Katayama / Terada / Yorino / Bohren / Downing / Mandeville | Mazda Technical Center | | Mazda | RX-7 | | Mazda | GTU | |