| 1 | Miles / Ruby | Shelby American Inc. (USA) | | Ford | GT-X1 | | Ford | P+5.0 |
| 2 | Gurney / Grant | Shelby American Inc. (USA) | | Ford | Mk II | | Ford | P+5.0 |
| 3 | Hansgen / Donohue | Holman & Moody (USA) | | Ford | Mk II | | Ford | P+5.0 |
| 4 | Foyt / Bucknum | Holman & Moody (USA) | | Ford | Mk II | | Ford | P+5.0 |
| 6 | Grossman / Lowther | Scuderia Bear | | Shelby | Cobra | roadster | Ford | S+5.0 |
| 7 | Bentley / Latta / Byrne | Space Science Service (USA) | | Shelby | Cobra | | Ford | S+5.0 |
| 8 | Yenko / Morgan / Whims | Harold C. Whims (USA) | | Chevrolet | Corvette Sting Ray | C2 | Chevrolet | GT+5.0 |
| 9 | Wintersteen / Moore | Roger Penske (USA) | | Chevrolet | Corvette Sting Ray | C2 | Chevrolet | GT+5.0 |
| 10 | Thompson / Guldstrand | Roger Penske (USA) | | Chevrolet | Corvette Grand Sport | | Chevrolet | P+5.0 |
| 11 | Sharp / Hall | Chaparral Cars Inc. (USA) | | Chaparral | 2D | | Chevrolet | P+5.0 |
| 12 | Bonnier / Hill | Chaparral Cars Inc. (USA) | | Chaparral | 2D | | Chevrolet | P+5.0 |
| 17 | Wietzes / Fisher | Comstock Racing Team (CDN) | | Ford | GT40 | | Ford | S5.0 |
| 18 | McLean / Ouellet | Comstock Racing Team (CDN) | | Ford | GT40 | | Ford | S5.0 |
| 19 | Scott / Revson | Essex Wire Corporation (USA) | Skip Scott | Ford | GT40 | | Ford | S5.0 |
| 20 | Gregory / Pabst | Essex Wire Corporation (USA) | Skip Scott | Ford | GT40 | | Ford | S5.0 |
| 21 | Ireland / Sutcliffe | Peter Sutcliffe | | Ford | GT40 | | Ford | S5.0 |
| 22 | Wonder / Brown | Bill Wonder (USA) | | Ford | GT40 | | Ford | S5.0 |
| 23 | Jennings / Holquist / *Koveleski | Scuderia Bear (USA) | William McKelvy | Ford | GT40 | | Ford | S5.0 |
| 24 | Hill / Stewart | Alan Mann Racing (GB) | Alan Mann | Ford | GT40 | | Ford | S5.0 |
| 25 | Whitmore / Gardner / *Amon | Alan Mann Racing (GB) | | Ford | GT40 | | Ford | S5.0 |
| 26 | Rodriguez / Andretti | North American Racing Team (USA) | | Ferrari | 365 P2 | | Ferrari | P5.0 |
| 27 | Parkes / Bondurant | SpA Ferrari SEFAC (I) | Enzo Ferrari | Ferrari | 330 P3 | Barchetta | Ferrari | P5.0 |
| 30 | Hudson / Gillebard | Frans Gillebard | | Ferrari | 330 P | | Ferrari | P5.0 |
| 31 | Hull / Kingham | Jaguar Cars of Winter Haven (USA) | | Jaguar | E-type | | Jaguar | GT5.0 |
| 32 | Rodgers / Buchman / Robson | Richard B. Robson (USA) | Richard Robson | Jaguar | E-type | | Jaguar | GT5.0 |
| 33 | Swanson / Ennis | Arthur W. Swanson | | Ferrari | 250 LM | | Ferrari | S5.0 |
| 34 | O'Brien / Parsons | Don Fong | | Ferrari | 275 P | | Ferrari | P5.0 |
| 35 | Slottag / Perkins | Jack Slottag | | Ferrari | 250 GTO | | Ferrari | S3.0 |
| 36 | MacGrotty / Riley / Myers | Ross MacGrotty Chevrolet (USA) | | Yenko | Stinger | | Chevrolet | P3.0 |
| 37 | Mims / Luke | McMillan Ring Free Oil Co. (USA) | | Yenko | Stinger | | Chevrolet | P3.0 |
| 38 | Arutunoff / Crow | Anatoly Arutunoff (USA) | | Lancia | Flaminia | Sport Zagato | Lancia | GT2.5 |
| 39 | Tullius / Gates | Standard Triumph Motor Co. | | Triumph | TR4 | A | Triumph | P3.0 |
| 40 | Gilmartin / Rothschild | Standard Triumph Motor Co. | | Triumph | TR4 | A | Triumph | GT2.5 |
| 41 | Froines / Pendleton | Standard Triumph Motor Co. (GB) | | Triumph | TR4 | A | Triumph | GT2.5 |
| 42 | Heimrath / Hill | Standard Triumph Motor Co. | | Triumph | TR4 | A | Triumph | GT2.5 |
| 43 | Hall / Costner | Fergus Import Motors | | Morgan | Plus 4 | Super Sports | Triumph | P3.0 |
| 44 | Hopkirk / Hedges / *Manton / *Brown | British Motor Co. | | MG | B | | BMC | P3.0 |
| 46 | Scarfiotti / Bandini | SpA Ferrari SEFAC (I) | | Ferrari | Dino 206 S | | Ferrari | P2.0 |
| 47 | Cunningham / Jordan / Fitch | Briggs Cunningham | | Porsche | 904 | GTS | Porsche | S2.0 |
| 48 | Wester / Patrick / *Jordan | Otto Zipper | | Porsche | 906 | | Porsche | P2.0 |
| 49 | Siffert / Vögele | Charles Vögele | | Porsche | 906 | | Porsche | P2.0 |
| 50 | Underwood / Hugus | Ed Hugus | | Porsche | 906 | | Porsche | P2.0 |
| 51 | Ryan / Coleman / *Bencker | RBM Motors (USA) | Jack Ryan | Porsche | 911 | Coupé 901 | Porsche | GT2.0 |
| 52 | Herrmann / Buzzetta / Mitter | Porsche System Engineering (D) | | Porsche | 906 | | Porsche | P2.0 |
| 53 | Mitter / Klass | Porsche System Engineering (D) | | Porsche | 906 | | Porsche | P2.0 |
| 54 | Follmer / Gregg | Porsche Germany (D) | | Porsche | 904 | GTS | Porsche | S2.0 |
| 55 | Schütz / Glemser | Porsche System Engineering (D) | | Porsche | 904 | GTS | Porsche | S2.0 |
| 56 | Duval / Kroll / *Saskal | Jacques Duval (CDN) | | Porsche | 904 | GTS | Porsche | S2.0 |
| 57 | Ripley / Wetanson | Wetanson & Ripley | | Porsche | 904 | GTS | Porsche | S2.0 |
| 58 | McKemie / Opert | Carl Haas Automobiles (USA) | | Elva | Courier | Mk IV | Ford | S2.0 |
| 59 | Mac / Manton / *Hedges / *Brown | British Motor Co. | | MG | B | | BMC | GT2.0 |
| 60 | Colombosian / Todd | Autolab Imports (USA) | | Lotus | Elan | | Ford | GT1.6 |
| 61 | Zeccoli / "Geki" | Autodelta SpA (I) | | Alfa Romeo | Giulia TZ2 | | Alfa Romeo | S1.6 |
| 62 | Bianchi / Consten | Autodelta SpA (I) | | Alfa Romeo | Giulia TZ2 | Competition FIA GT Berlinetta | Alfa Romeo | S1.6 |
| 63 | "Geki" / Andrey / *de Adamich / *Bussinello | Autodelta SpA (I) | | Alfa Romeo | Giulia TZ2 | | Alfa Romeo | S1.6 |
| 64 | Posey / Theodoracopulos | Filippo Theodoli (USA) | | Alfa Romeo | Giulia TZ2 | | Alfa Romeo | S1.6 |
| 65 | Baker / Kirtley | Fred J. Baker (USA) | | Alpine | A110 | 1300 | Renault | S1.3 |
| 66 | Aaltonen / Baker | Donald Healey Motor Co. (GB) | | Austin-Healey | Sprite | | BMC | P2.0 |
| 67 | Hawkins / Mäkinen | Donald Healey Motor Co. (GB) | | Austin-Healey | Sprite | | BMC | P2.0 |
| 68 | Hanna / Decker / *Waltman | Howard Hanna | | Matra | Djet | 5S | Renault | S1.3 |
| 69 | Sellers / Shaw | Capt. Kenneth Sellers | | Alpine | A110 | 1100 | Renault | S1.3 |
| 80 | Said / Cuomo / Addison / *Payne / *Salo | Tom Payne (USA) | Tom Payne | Shelby | Cobra | | Ford | S5.0 |
| 82 | Kohler / Reina / Biddle / *Behm | Terry Kohler (USA) | | Shelby | GT350 | R | Ford | GT5.0 |
| 84 | West / Charles | Roger West (USA) | | MG | B | | BMC | GT2.0 |
| 85 | Ackerly / McNeill | Continental Cars Ltd. (GB) | | MG | B | | BMC | GT2.0 |
| 87 | Kolb / Fulp / *Thorpe | Keymo Motors Corporation (USA) | | Porsche | 904 | /8 Bergspyder | Porsche | P2.0 |
| 89 | Schantz / Smith | Sherman S. Smith | | Abarth-Simca | 1300 | Bialbero | Abarth | S1.3 |
| 92 | Vega / Kingham / Byrne | John Kingham (USA) | | Triumph | TR4 | A | Triumph | GT2.5 |