| 0 | Barilla / *Lanier / *Moretti | Joest Racing (D) | Reinhold Joest | Porsche | 962 | Porsche | GTP |
| 00 | Adams / Los / Hotchkis | Hotchkis Racing (USA) | | March | 83G | Porsche | GTP |
| 01 | Bell / Wolters / Carter | AT & T | | Royale | RP40 | Buick | Lights |
| 02 | Stevens / Sereix / Newsome / Kreider | Roy Newsome Racing | | Mazda | RX-7 | Mazda | GTU |
| 04 | Schuppan / Redman / Haywood | Group 44 (USA) | | Jaguar | XJR-7 | Jaguar | GTP |
| 06 | Morejon / Varde / Almeida | Hi-Tech Racing (USA) | Bill McDill | Porsche | 935 | Porsche | GTP |
| 07 | Pruett / Ludwig / Jenner | 7-Eleven/Roush Racing (USA) | | Ford | Mustang | Ford | GTO |
| 2 | Leon / Grohs / Fitzgerald / *Leon | Leon Brothers Racing (USA) | | March | 85G | Porsche | GTP |
| 3 | Boutsen / Larrauri / *Sigala | Brun Motorsports (CH) | Thompson | Porsche | 962 | Porsche | GTP |
| 4 | Price / Mullen / Whetstine | Lee Racing | | Chevrolet | Corvette GTP | Chevrolet | GTP |
| 5 | Stuck / *Akin / *Gartner | Bob Akin Motor Racing (USA) | | Porsche | 962 | Porsche | GTP |
| 6 | Morgan / Blackburn / Simpson | Morgan Performance (USA) | | Tiga | GT286 | Buick | Lights |
| 8 | Foyt / Luyendyk / Sullivan / Henn | Henn's Swap Shop Racing (USA) | Preston Henn | Porsche | 962 | Porsche | GTP |
| 9 | Brockman / Durst / Gregg / Trueman | Rinzler Motoracing (USA) | | Tiga | GT285 | Mazda | Lights |
| 10 | Leeward / Adam / Mead | Leeward Racing (USA) | Jim Leeward | March | 82G | Chevrolet | GTP |
| 11 | Lewis / *Kendall / *Kendall / *Jones | Kendall Racing (USA) | Chuck Kendall | Lola | T616 | Mazda | Lights |
| 13 | Rubino / Mummery / Schneider | Outlaw Racing (USA) | | Argo | JM19 | Mazda | Lights |
| 14 | Holbert / Bell / Unser, Jr. | Holbert Racing (USA) | | Porsche | 962 | Porsche | GTP |
| 16 | Olson / Cobb / Dyson | Dyson Racing (USA) | | Porsche | 962 | Porsche | GTP |
| 17 | Bacon / Scott / Krueger | Al Bacon Racing (USA) | Al Bacon | Mazda | RX-7 | Mazda | GTU |
| 25 | Peters / *Painter / *Nehl / *Gaylord | Lucas Truck Service | | Chevrolet | Camaro | Chevrolet | GTO |
| 26 | Bupp / Hayes-Harlow / Taylor | Walter Johnston (USA) | | Pontiac | Firebird | Pontiac | GTO |
| 27 | Cowart / Miller / Fowells | M S B Racing (USA) | | Argo | JM19 | Mazda | Lights |
| 28 | Labonte / *Gant / *Parsons | Texas Enterprises/US Tobacco | | Oldsmobile | Calais | Oldsmobile | GTO |
| 29 | Kimbrough / Gennone / Overbagh / Baljet | OMR Engines | | Chevrolet | Camaro | Chevrolet | GTO |
| 30 | McCall / Carter / Mueller / Sheehy | Skoal Bandit | | Chevrolet | Camaro | Chevrolet | GTO |
| 32 | Leitzinger / Carder / Baldwin / Alexander | Alderman Nissan | | Nissan | 280ZX | Nissan | GTU |
| 33 | Boand / Anderson / Allen | Bo-And Racing | | Lola | T600 | Chevrolet | GTP |
| 34 | Fonseca / Mendez / "Jamsal" | Latino Racing (DR) | Kikos Fonseca | Porsche | 934 | Porsche | GTO |
| 35 | Gonzalez / Soto / Davila / Montoya | Xtra Super Food CNT | | Royale | RP40 | Porsche | Lights |
| 36 | Panaccione / *Case | Case Racing (USA) | | Porsche | 924 | Porsche | GTU |
| 37 | Welter / Newsome / Burdsall | Burdsall-Newsome Racing | | Tiga | GT285 | Mazda | Lights |
| 38 | Mandeville / Smith / Febles | Mandeville Auto Tech (USA) | Roger Mandeville | Mazda | RX-7 | Mazda | GTU |
| 43 | Cohen / Christian / Congleton | Global American | | BMW | M1 | BMW | GTO |
| 44 | Tullius / Ballot-Léna / Robinson | Group 44 (USA) | | Jaguar | XJR-7 | Jaguar | GTP |
| 44T | | Group 44 (USA) | | Jaguar | XJR-7 | Jaguar | GTP |
| 45 | Paul, Jr. / Ganassi / Capelli / Ganz | RC Buick Hawk/Conte (USA) | | March | 85G | Buick | GTP |
| 46 | Ganz / Madren / *Lobenberg | RC Buick Hawk/Conte (USA) | | March | 85G | Buick | GTP |
| 47 | Millen / Forbes-Robinson / Riggins | Dingman Bros Racing (USA) | | Pontiac | Firebird | Pontiac | GTO |
| 48 | Walker / Goellnicht / Monk | Global American (USA) | Don Walker | March | 83G | Chevrolet | GTP |
| 50 | Elliot / Rudd / Petty / Schrader | Folgers/Motorcraft (USA) | | Ford | Mustang | Ford | GTO |
| 52 | van der Merwe / Bundy / Dallenbach, Jr. | Hendrick Motorsports (USA) | | Chevrolet | Corvette GTP | Chevrolet | GTP |
| 54 | Durkheimer / Auberlen / Eisenlohr / Jauker | S-P Racing/Escort (USA) | | Porsche | 911 Carrera | Porsche | GTU |
| 55 | Heinz / Zwiren / Yenko / Thompson | Dave Heinz Imports | | Chevrolet | Corvette | Chevrolet | GTO |
| 56 | Montoya / Naon, Jr. / Migoya | Ricardo Londono (CO) | | Pontiac | Firebird | Pontiac | GTO |
| 57 | Kryder / Palmer / Staffilino / Whelan | Kryderacing (USA) | Reed Kryder | Nissan | 280ZX | Nissan | GTU |
| 62 | Coconis / Robles / Marte | Roush Racing (USA) | | Ford | Mustang | Ford | GTO |
| 63 | Downing / O'Steen / Maffucci | Certified Brakes (USA) | | Argo | JM19 | Mazda | Lights |
| 64 | Mueller / Hassey / Hester | Raintree Corporation (USA) | | Ford | Mustang | Ford | GTO |
| 66 | Rothbarth / Kline / Meyer | STS-Mike Meyer Racing | | Royale | RP40 | Mazda | Lights |
| 67 | Warwick / Brassfield / Busby / Mass | B.F. Goodrich (USA) | | Porsche | 962 | Porsche | GTP |
| 68 | Lammers / Morton / Warwick / *Mass | B.F. Goodrich (USA) | | Porsche | 962 | Porsche | GTP |
| 71 | Johnson / Shaw / Dunham | Team Highball (USA) | | Mazda | RX-7 | Mazda | GTU |
| 72 | Bergstrom / Felton / Gentilozzi | Whitehall Rocketsports (USA) | Paul Gentilozzi | Oldsmobile | Toronado | Oldsmobile | GTO |
| 74 | McDill / McDill / Juckette | Bill McDill | | Chevrolet | Camaro | Chevrolet | GTO |
| 75 | Reed / Kendall / Hogdal / *Rinzler | CCR (USA) | | Mazda | RX-7 | Mazda | GTU |
| 76 | Northam / Walker / Rubright | Walker Racing | | Chevrolet | Corvette | Chevrolet | GTO |
| 77 | Franchi / Gentile / Knoop / *Newsum | Brooks Racing | | Ford | Thunderbird | Ford | GTO |
| 78 | Uria / Figaro / Refenning | 901 Racing (USA) | | Porsche | 911 Carrera | Porsche | GTU |
| 80 | Finotto / Melgrati / Coppelli / *Facetti | Carma Racing (I) | | Alba | AR6 | Ferrari | Lights |
| 82 | Wessel / Kennedy / Fuller / Keck | K & P Racing | | Chevrolet | Corvette | Chevrolet | GTP |
| 83 | Reisman / Hebert / Gaffney / Stone | Import Restorations | | Pontiac | Firebird | Pontiac | GTO |
| 86 | Wollek / Daly / Leven | Bayside Disposal Racing (USA) | | Porsche | 962 | Porsche | GTP |
| 87 | Grable / Knowles / Heinricy / Carradine | Morrison Cook Motorsport (USA) | | Chevrolet | Corvette | Chevrolet | GTO |
| 88 | Baldwin / McConnell / Morrison / Knowles / *Carradine | Morrison Cook Motorsport | | Chevrolet | Corvette | Chevrolet | GTO |
| 89 | Hunt / Shelton / Romano / *Boy | Tom Hunt | | Mazda | RX-7 | Mazda | GTU |
| 90 | Delano / Petery | Road Circuit Technology | | Pontiac | Firebird | Pontiac | GTO |
| 92 | Tisdelle / *Van Every / *Bond | Van Every Racing (USA) | | Chevrolet | Camaro | Chevrolet | GTO |
| 93 | Pawley / Marsh / Marsh | Mid O/Rusty Jones (USA) | | Argo | JM16 | Mazda | Lights |
| 98 | Aase / Cord | All American Racers (USA) | | Toyota | Celica Turbo | Toyota | GTO |
| 99 | Andrews / Phillips / Bain | R. B. Promotions (GB) | | Tiga | GC285 | Ford | GTP |