| 0 | Moretti / *Lanier / *"Winter" | Momo/Joest Racing (D) | Reinhold Joest | Porsche | 962 | | Porsche | GTP |
| 00 | Adams / Hotchkis / Kalagian | Hotchkis Racing (USA) | John Hotchkis | March | 83G | | Porsche | GTP |
| 01 | Andrey / Herlin / Mancuso / *Coppelli | Gaston Andrey Racing | | Alba | AR2 | | Ferrari | Lights |
| 02 | Dallenbach, Jr. / Byrne | Spirit Racing | | Chevrolet | Camaro | | Chevrolet | GTO |
| 04 | Redman / Schuppan / Haywood | Group 44 (USA) | | Jaguar | XJR-7 | | Jaguar | GTP |
| 04T | | Group 44 (USA) | | Jaguar | XJR-7 | | Jaguar | GTP |
| 05 | Kendall / White / Frank | Jerry Kendall (USA) | Jerry Kendall | Porsche | 935 | -84 | Porsche | GTP |
| 08 | Romano / Freeman / Nelson | Simms-Romano Enterprises (USA) | | Mazda | RX-7 | | Mazda | GTU |
| 4 | Mullen / *Price / *Baird | Lee Racing | | Chevrolet | Corvette GTP | | Chevrolet | GTP |
| 5 | Akin / Stuck / Gartner | Bob Akin Motor Racing (USA) | | Porsche | 962 | | Porsche | GTP |
| 6 | Morgan / Blackburn | Morgan Performance (USA) | | Tiga | GT286 | | Buick | Lights |
| 7 | Pruett / Jenner | 7-Eleven/Roush Racing (USA) | Jack Roush | Ford | Mustang | | Ford | GTO |
| 8 | Olson / Foyt | Henn's Swap Shop Racing (USA) | Preston Henn | Porsche | 962 | | Porsche | GTP |
| 9 | Moore / Overbagh / Gennone | OMR Engines (USA) | Hoyt Overbagh | Chevrolet | Camaro | III | Chevrolet | GTO |
| 11 | Kendall / Lewis / Jones | Kendall Racing (USA) | Chuck Kendall | Lola | T616 | | Mazda | Lights |
| 12 | Hobbs / Watson | BMW North America | | BMW | GTP | | BMW | GTP |
| 13 | Rubino / Mummery / *Smith | Outlaw Racing Team (USA) | | Argo | JM19 | | Mazda | Lights |
| 14 | Holbert / Bell / Unser, Jr. | Holbert Racing (USA) | Al Holbert | Porsche | 962 | | Porsche | GTP |
| 16 | Hinze / Newsum / Blackaller | MHR Racing (USA) | Marty Hinze | Porsche | 935 | K3 | Porsche | GTP |
| 17 | Bacon / Scott / Krueger | Al Bacon Racing (USA) | Al Bacon | Mazda | RX-7 | | Mazda | GTU |
| 18 | Rahal / Watson | BMW North America (D) | | BMW | GTP | | BMW | GTP |
| 19 | Andretti / Jones | BMW North America (D) | | BMW | GTP | | BMW | GTP |
| 21 | Hofstra / Slater / Robinson | Wonzer Racing (USA) | | Porsche | 911 | | Porsche | GTU |
| 22 | Corazzo / Flemke / Hessert | Team 22/Sherri Cup (USA) | | Royale | RP40 | | Mazda | Lights |
| 24 | Ruesch / *Gralia / *Andrea / *Clark | Global Racing | | Mazda | RX-7 | | Mazda | GTU |
| 25 | Nehl / Fortin / Gaylord | Lucas Truck Service | | Chevrolet | Camaro | | Chevrolet | GTO |
| 26 | Taylor / Hackney / Albanese | Bob's Speed Products | | Pontiac | Firebird | | Pontiac | GTO |
| 27 | Fowells / Cowart / Miller | MSB Racing (USA) | | Argo | JM19 | | Mazda | Lights |
| 28 | Labonte / Parsons / Parsons | Texas Enterprises/US Tobacco | | Oldsmobile | Calais | | Oldsmobile | GTO |
| 29 | Canizares / Jacobson / Katz | Ares Sports | | Tiga | GT285 | | Mazda | Lights |
| 30 | Carter / McCall / Sheehy / Bohren | Skoal Bandits | | Chevrolet | Camaro | III | Chevrolet | GTO |
| 31 | Bupp / Church / Generotti | CRT Contracting Corporation (USA) | | Chevrolet | Camaro | | Chevrolet | GTO |
| 34 | Fonseca / Mendez / "Jamsal" | Latino Racing (CR) | Kikos Fonseca | Porsche | 934 | | Porsche | GTO |
| 35 | Griffin / Hefner / Winfree | Team Dallas | | Porsche | 911 Carrera | RSR | Porsche | GTU |
| 36 | Case / Panaccione | Case Racing (USA) | | Porsche | 924 | Carrera GTR | Porsche | GTU |
| 37 | Newsome / Burdsall / Welter | Burdsall/Newsome Racing | | Tiga | GT285 | | Mazda | Lights |
| 38 | Mandeville / Smith | Mandeville Auto Tech (USA) | Roger Mandeville | Mazda | RX-7 | | Mazda | GTU |
| 39 | Brezinka / Bartling / Centeno | R & H Racing (CDN) | | Porsche | 911 | | Porsche | GTU |
| 41 | Wallace / McDonald / Bruce | Lion Rampant (USA) | Chaunce Wallace | Mazda | RX-7 | | Mazda | GTU |
| 42 | Higgins / Mead / Cherry | White/Allen Porsche | | Fabcar | CL | | Porsche | Lights |
| 44 | Tullius / Robinson / Ballot-Léna | Group 44 (USA) | | Jaguar | XJR-7 | | Jaguar | GTP |
| 45 | Galeano / Jacobs / Cardenas | Turbo Concepts | | Porsche | 911 | | Porsche | GTU |
| 46 | Paul, Jr. / Ganz / Madren | R C Buick Hawk (USA) | | March | 85G | | Buick | GTP |
| 47 | Forbes-Robinson / Riggins | Dingman Bros Racing (USA) | | Pontiac | Firebird | | Pontiac | GTO |
| 48 | Wonzer / Pagan / Dewey / Cripe | Gary Wonzer (USA) | Gary Wonzer | Porsche | 911 Carrera | RSR | Porsche | GTO |
| 50 | Elliot / Rudd | Roush/Folger's/Motorcraft (USA) | | Ford | Mustang | | Ford | GTO |
| 51 | Heinz / Yenko / Zwiren | Dave Heinz Imports (USA) | | Chevrolet | Corvette | | Chevrolet | GTO |
| 54 | Auberlen / Jauker / Eisenlohr / Durkheimer | S P Racing (USA) | | Porsche | 911 Carrera | | Porsche | GTU |
| 55 | Rubright / *Walker / *Northam | Bud Light Corvette | | Chevrolet | Corvette C4 | | Chevrolet | GTO |
| 56 | Henderson / Lee / Costanzo | Hi -Fi Hospital (USA) | | Chevrolet | Camaro | | Chevrolet | GTO |
| 57 | Kryder / Palmer / Morici | Kryderacing | | Nissan | 280ZX | | Nissan | GTU |
| 58 | Borlase / Torres / Hammond | Rick Borlase (USA) | Rick Borlase | Porsche | 934 | | Porsche | GTO |
| 60 | Mendez / DeNarvaez | Latino Racing (DR) | | Porsche | 911 Carrera | RSR | Porsche | GTU |
| 61 | O'Neill / Shelton / Courtney | Deco Sales (USA) | Brent O'Neill | Argo | JM16 | | Buick | Lights |
| 62 | Marte / Coconis | Roush Racing (USA) | | Ford | Mustang | | Ford | GTO |
| 63 | Downing / Maffucci / O'Steen | Certified Brakes Racing (USA) | | Argo | JM19 | | Mazda | Lights |
| 64 | Hester / Hassey | Raintree Corporation (USA) | | Ford | Mustang | | Ford | GTO |
| 66 | Rothbarth / Meyer / Kline | STS-Mike Meyer Racing | | Royale | RP40 | | Mazda | Lights |
| 67 | Brassfield / Morton / Busby | B F Goodrich (USA) | Jim Busby | Porsche | 962 | | Porsche | GTP |
| 68 | Busby / Larrauri | B F Goodrich (USA) | | Porsche | 962 | | Porsche | GTP |
| 69 | Gardner / Greene / Noffke | Rick Balderson | | Chevrolet | Monza | | Chevrolet | GTO |
| 71 | Johnson / Shaw / Dunham | Team Highball (USA) | Amos Johnson | Mazda | RX-7 | | Mazda | GTU |
| 72 | Bergstrom / *Gentilozzi / *Felton / *Winters | Whitehall-Rocketsports (USA) | Paul Gentilozzi | Oldsmobile | Toronado | | Oldsmobile | GTO |
| 73 | Munoz / Migoya / Albiza | Eurospec Imports | | Chevrolet | Camaro | | Chevrolet | GTO |
| 75 | Reed / Kendall / Hogdal | C C R (USA) | | Mazda | RX-7 | | Mazda | GTU |
| 76 | Baldwin / Miller | Peerless Racing (USA) | | Chevrolet | Camaro | | Chevrolet | GTO |
| 77 | Loving / *Lee | Sunrise Racing | | Chevrolet | Camaro | | Chevrolet | GTO |
| 78 | Uria / Figaro / Refenning | 901 Racing (USA) | | Porsche | 911 Carrera | RSR | Porsche | GTU |
| 79 | McKitterick / Koll | Whitehall-Rocketsports | | Alba | AR5 | | Chevrolet | Lights |
| 80 | Finotto / Facetti / Melgrati | Gaston Andrey Racing | | Alba | AR6 | | Ferrari | Lights |
| 82 | Fuller / Montgomery / *Keck | K & P Racing (USA) | Karl Keck | Chevrolet | Corvette | C3 | Chevrolet | GTP |
| 83 | Shafer / Maloy / McVay | Shafer Racing (USA) | Craig Shafer | Chevrolet | Camaro | III | Chevrolet | GTO |
| 85 | Boyer / Roberts / Rand / Unser | Highlands County Racing | | Pontiac | Firebird | | Pontiac | GTO |
| 86 | Wollek / Barilla / *Leven | Bayside Disposal Racing (USA) | Bruce Leven | Porsche | 962 | | Porsche | GTP |
| 87 | Knowles / McConnell / Morrison / *Grable / *Heinricy / *Carradine | Morrison Cook Motorsport (USA) | | Chevrolet | Corvette | | Chevrolet | GTO |
| 88 | Grable / Heinricy / Carradine / *Knowles / *McConnell / *Morrison | Morrison Cook Motorsport (USA) | | Chevrolet | Corvette | | Chevrolet | GTO |
| 89 | Hunt / Shelton | Team Hunt Racing | | Mazda | RX-7 | | Mazda | GTU |
| 90 | Delano / Nightingale / Moise | Road Circuit Technology | | Chevrolet | Camaro | | Chevrolet | GTO |
| 91 | Tomlinson / Finger / Finger | Foreign Matter Racing | | Mazda | RX-7 | | Mazda | GTU |
| 92 | Van Every / Tisdelle / Bond | Van Every Racing (USA) | | Chevrolet | Camaro | | Chevrolet | GTO |
| 93 | Marsh / Pawley / *Marsh | Mid-O Racing (USA) | | Argo | JM16 | | Mazda | Lights |
| 96 | Lee / Julian / Lee / Saxon | Bob's Speed Products | | Buick | Skyhawk | | Buick | GTO |
| 98 | Cord / Aase | All American Racers (USA) | Dan Gurney | Toyota | Celica | Mk III Turbo | Toyota | GTO |
| 99 | Los / Wood | Roy Baker Promotions (GB) | | Tiga | GC285 | | Ford | GTP |