| 1st | 25 | Chris Amon / Mario Andretti | Ferrari 312 P | Ferrari S.P.A. SEFAC | 2:40.1400 |
| 2nd | 9 | Ronnie Bucknum / Mark Donohue | Lola T70 Mk.3B GT Chevrolet | Roger Penske Racing Enterprises | 2:40.9200 |
| 3rd | 29 | Gerhard Mitter / Udo Schütz | Porsche 908/02 | Porsche System Engineering Ltd. | 2:42.7700 |
| 4th | 31 | Jo Siffert / Brian Redman | Porsche 908/02 | Porsche System Engineering Ltd. | 2:42.9000 |
| 5th | 10 | Scooter Patrick / Dave Jordan | Lola T70 Mk.3 GT Chevrolet | American International Racing, Inc. | 2:43.4400 |
| 6th | 11 | Lothar Motschenbacher / Ed Leslie | Lola T70 Mk.3 GT Chevrolet | American International Racing, Inc. | 2:44.0500 |
| 7th | 14 | Ulf Norinder / Jo Bonnier | Lola T70 Mk.3B GT Chevrolet | Sportscars Switzerland | 2:44.3700 |
| 8th | 30 | Vic Elford / Richard Attwood | Porsche 908/02 | Porsche System Engineering Ltd. | 2:44.3800 |
| 9th | 28 | Hans Herrmann / Kurt Ahrens, Jr. / Rolf Stommelen | Porsche 908/02 | Porsche System Engineering Ltd. | 2:44.5100 |
| 10th | 32 | Mario Casoni / Andrea de Adamich | Alfa Romeo T33/3 | Autodelta, S.P.A. | 2:45.6400 |
| 11th | 27 | Rolf Stommelen / Joe Buzzetta / Kurt Ahrens, Jr. | Porsche 908/02 | Porsche System Engineering Ltd. | 2:45.6700 |
| 12th | 22 | Jackie Oliver / Jacky Ickx | Ford GT40 | J. W. Automotive Engineering Ltd. | 2:47.4300 |
| 13th | 23 | David Hobbs / Mike Hailwood | Ford GT40 | J. W. Automotive Engineering Ltd. | 2:47.7400 |
| 14th | 33 | Nino Vaccarella / Lucien Bianchi | Alfa Romeo T33/3 | Autodelta, S.P.A. | 2:47.9500 |
| 15th | 34 | Nanni Galli / Ignazio Giunti | Alfa Romeo T33/3 | Autodelta, S.P.A. | 2:51.3600 |
| 16th | 44 | Alex Soler-Roig / Rudi Lins | Porsche 907 2.2 | Escuderia Nacional C.S. | 2:54.5500 |
| 17th | 1 | Tony DeLorenzo / Jerry Thompson | Chevrolet Corvette | Troy Promotions, Inc. | 3:00.3000 |
| 18th | 45 | Fred Baker / Dick Smothers | Porsche 906 E | Smothers Brothers Racing Team | 3:01.1300 |
| 19th | 26 | Pedro Rodriguez / Chuck Parsons | Ferrari 250 P | N.A.R.T. | 3:01.3600 |
| 20th | 2 | Dick Lang / Gib Hufstader | Chevrolet Corvette | Troy Promotions, Inc. | 3:01.5900 |
| 21st | 4 | Or Costanzo / Dave Heinz | Chevrolet Corvette | Or Costanzo | 3:02.2700 |
| 22nd | 5 | Don Yenko / Bob Grossman | Chevrolet Camaro Z/28 | Best Photo Service | 3:03.2100 |
| 23rd | 3 | Ed Lowther / Robert D. Esseks / Frank Dominianni | Chevrolet Corvette | Robert D. Esseks | 3:03.8900 |
| 24th | 18 | Wilton T. Jowett, Jr. / Bob Tullius | Chevrolet Camaro | Wilton T. Jowett, Srov. | 3:05.9200 |
| 25th | 37 | Ricardo Rodriguez / Charlie Kolb | Ferrari Dino 206 S | N.A.R.T. | 3:07.2400 |
| 26th | 46 | Armando Capriles / Alfredo Atencio | Porsche 906 E | Escuderia Manana | 3:07.3600 |
| 27th | 17 | Vince Gimondo / John Tremblay | Chevrolet Camaro I | Bruce Behrens Racing Enterprises | 3:09.1400 |
| 28th | 57 | Umberto Maglioli / Hugh Kleinpeter / Bob Beatty | Chevron B8 BMW | Raceco | 3:09.4900 |
| 29th | 38 | Sam Posey / Bob Dini | Ferrari Dino 206 GT | N.A.R.T. | 3:11.2700 |
| 30th | 48 | Mike Rahal / Bill Stroh / Hugh Wise | Porsche 906 | Nationwide of Chicago Food Brothers, Inc. | 3:12.3300 |
| 31st | 21 | Larry Dent / Larry Bock | Chevrolet Camaro | Larry Drover, (Laural Racing) | 3:12.5700 |
| 32nd | 24 | Francis Grant / Dieter Oest | Ford GT40 | Auto Enterprizes | 3:13.4500 |
| 33rd | 20 | David McClain / Don Kerney | Chevrolet Camaro | David H. McClain | 3:14.1900 |
| 34th | 19 | Maurice Carter / Nat Adams | Chevrolet Camaro | Maurice Carter Chevrolet | 3:17.2700 |
| 35th | 50 | Jacques Duval / George Nicholas | Porsche 911 T | Grand Prix Motor Oil | 3:17.4600 |
| 36th | 90 | Jim Netterstrom / Bruce Jennings / Mike Downs | Porsche 911 | P.A.R.T. | 3:19.7100 |
| 37th | 47 | Bob Bailey / Jim Locke | Porsche 911 T | P.A.R.T. | 3:20.3700 |
| 38th | 52 | Gérard Larrousse / André Wicky / Jean Sage | Porsche 911 T | Wicky Racing Team | 3:20.6400 |
| 39th | 51 | Gregg Loomis / Pete Harrison / Jack Ryan | Porsche 911 S | RBM Motors | 3:20.9300 |
| 40th | 53 | Wilbur Pickett / Peter Gregg | Porsche 911 | Wilbur Pickett | 3:21.1600 |
| 41st | 94 | Robin Ormes / Norberto Mastandrea | Chevrolet Camaro | Norberto Mastandrea (Freeport Bahama Racing Team) | 3:24.1200 |
| 42nd | 36 | Bill Brack / Craig Hill | MGC | British Leyland Motor Corporation | 3:26.7400 |
| 43rd | 43 | Ray Heppenstall / Howard Brown | Heppenstall Special Volkswagen | LeHigh Acres | 3:27.0400 |
| 44th | 16 | Richard Stevens / Robert Barg | Chevrolet Camaro | Richard Stevens | 3:27.1400 |
| 45th | 84 | George Drolsom / Harold Williamson | Porsche 911 | Dr. Harold Williamson | 3:27.2100 |
| 46th | 58 | Ed Hugus / Chuck Dietrich / Eugene Nearburg | BMW 2002 | Elsco Corporation | 3:27.5300 |
| 47th | 65 | Claudio Maglioli / Raffaele Pinto | Lancia Fulvia Sport Competizione | Algar Enterprises, Inc. | 3:29.0000 |
| 48th | 71 | Jim Baker / Paul Richards / Clive Baker | Austin-Healey Sprite | Ring Free Oil Racing Team | 3:30.2800 |
| 49th | 35 | Andrew Hedges / Paddy Hopkirk | MGC GT | British Leyland Motor Corporation | 3:30.3100 |
| 50th | 54 | Paul Sanford / Fred Opert | Porsche 911 | Fred Opert | 3:30.6500 |
| 51st | 66 | Innes Ireland / Mike Tillson / Howard Hanna | Lancia Fulvia Coupé 1,6HF | Algar Enterprises, Inc. | 3:35.4300 |
| 52nd | 59 | Smokey Drolet / Rosemary Smith | BMW 2002 | Elsco Corporation | 3:35.5700 |
| 53rd | 63 | Jim Gammon / Ray Mummery / Roger Houghton | MGB | Waldron Motors | 3:38.1300 |
| 54th | 72 | Janet Guthrie / Donna Mae Mims / Liane Engeman | Austin-Healey Sprite | Ring Free Oil Racing Team | 3:40.2000 |
| 55th | 68 | Bill Scott / Jim McDaniel / Steve Pieper | Zink VSR Volkswagen | H.R.H. Corp. | 3:41.0300 |
| 56th | 64 | Chris Waldron / Ben Scott / Dean Donley | MGB | Waldron Motors | 3:42.8200 |
| 57th | 88 | Randy Blessing / Don Cummings / Warren Stumes | Shelby GT350 | Donald C. Cummings | 3:43.5200 |
| 58th | 49 | Merv Rosen / Dave Morrell | Porsche 906 | Dr. Merv Rosen | 3:43.7100 |
| 59th | 69 | Reggie Smith / Tony Lilly / Don Pickett | Lotus Europa | John F. Howard | 3:46.3300 |
| 60th | 62 | Logan Blackburn / Jerry Truitt | MGB GT | British Leyland Motor Corporation | 3:47.1200 |
| 61st | 73 | Gregg Cameron / Ralph Kemmerer | Austin-Healey Sprite | Arthur Tuckerman | 3:48.3100 |
| 62nd | 99T | John Colgate / Don Parks | MGB | Gerry Racing Enterprise, Inc. | 3:52.1800 |
| 63rd | 41 | Armando DeAmbadgio / Sergio Trevale | Alfa Romeo GTA Junior | Escuderia Manana | 3:55.9500 |
| 64th | 85 | Richard Crebs / Ronald Strickler / Robert Whitaker | Alfa Romeo GTA | Richard Crebs | 4:02.2900 |
| 65th | 60 | Walter Brown / Buzz Marcus | Opel Rallye | Jim Cooke Buick & Opel | 4:08.0900 |
| 66th | 67 | Bill Boye / Russ Shirey | Beach 4B Volkswagen | Competition Components | 4:21.4100 |
| 67th | 6 | Garry R. Davis / Herbert R. Madray / Don Madray | Ford Mustang | Herbert R. Madray | no time |
| 68th | 7 | Charlie Rainville / Paul Pettey | Ford Mustang | Argento Racing Organization | no time |
| 69th | 98 | Ron Polimeni / Robert Theall | Volvo PV 544 | George W. Sanderson | no time |
| 71st | 93 | Craig Fisher / Serge Adams | Chevrolet Camaro | Todco Racing Canada Ltd. | no time |