| 1 | Lola T70 Mk.2 Ford | John W. Mecom Jr. | metallic blue (+dark blue/white) | | Firestone | | open | mid |
| 2 | Mirage Mark I A Oldsmobile | Jack Nethercutt | plum | | | | open | mid |
| 3 | Lola T70 Mk.2 Chevrolet | Team Surtees Ltd. | red (+white) | | Firestone | Shell | open | mid |
| 4 | McLaren Elva Mark IIB Chevrolet | Bruce McLaren Motor Racing Ltd. | red (+white) | | Firestone | Valvoline | open | mid |
| 5 | McLaren Elva Mark IIB Chevrolet | Bruce McLaren Motor Racing Ltd. | red (+white) | | Firestone | Valvoline | open | mid |
| 6 | Lola T70 Mk.2 Chevrolet | Roger Penske Racing Enterprises | dark blue (+yellow) | SUNOCO SPECIAL | Firestone | Sunoco | open | mid |
| 7 | Lola T70 Mk.2 Chevrolet | Team Surtees Ltd. | red (+white) | | Firestone | Shell | open | mid |
| 8 | Lola T70 Mk.2 Chevrolet | Sidney Taylor | white (+green) | SIDNEY TAYLOR | Firestone | | open | mid |
| 9 | Lola T70 Chevrolet | Hudson Enterprises | silver | SKIP HUDSON | Firestone | Valvoline | open | mid |
| 10 | McLaren Elva Mark II Chevrolet | Hilton Racing Team | red | | | Valvoline | open | mid |
| 11 | Genie Mk X B Chevrolet | Huffaken Automotive Engineering | yellow | | | | - | - |
| 15 | McKee Mk V Plymouth | Bob Montana | white | | | | open | mid |
| 16 | Lola T70 Mk.2 Chevrolet | George Follmer Enterprises | light metallic blue (+white) | | Firestone | | open | mid |
| 19 | McLaren Elva Mark II Mercury | Dick Niles | red/dark blue/white | | | | open | mid |
| 20 | McLaren Elva Mark II Ford | Drummond Racing Organization | | | | | open | mid |
| 23 | Lola T70 Mk.2 Ford | Alderman Automotive Service, Inc. | dark green (+white) | | | | open | mid |
| 24 | Ferrari Dino 206 S | Modern Classic Motors | red | | Goodyear | | closed | mid |
| 25 | Lola T70 Mk.2 Chevrolet | Epstein Enterprises Ltd. | light turquoise | | | | open | mid |
| 30 | Lola T70 Mk.2 Ford | All American Racers | dark blue (+white) | BARDAHL | Goodyear | Bardahl | open | mid |
| 32 | Porsche 906 | Douglas Revson | red/white/blue | SIGNS | | | closed | mid |
| 33 | McLaren Elva Mark II Ford | Autodynamics Corporation | red/white/blue | | | | open | mid |
| 38 | McLaren Elva Mark II Ford | Ecurie Greene, Inc. | green | | Goodyear | | open | mid |
| 39 | McLaren Elva Mark II Ford | Ludwig Heimrath | yellow | POWERED BY FORD | | | open | mid |
| 43 | Lola T70 Mk.2 Chevrolet | John W. Mecom Jr. | metallic blue (+dark blue/white) | | | | open | mid |
| 52 | Genie Mk X Ford | Eve & Jones Racing | ivory (+red) | BILL EVE/EARL JONES | | | open | mid |
| 53 | Lola T70 Mk.1 Chevrolet | Racing Partnerships (Jersey) Ltd. | red | | | Valvoline | open | mid |
| 56 | PAM GP7 Ford | Masterson Racing Enterprises | blue | PAM GP7/ALEXANDER KERR | Goodyear | | open | mid |
| 57 | Lola T70 Chevrolet | Monte R. Shelton | blue | | | | open | mid |
| 61 | McLaren Elva Mark II Ford | Bud Morley | dark blue | | | | open | mid |
| 62 | McLaren Elva Mark II Chevrolet | Gun Motor Racing, Ltd. | light green | | | Valvoline | open | mid |
| 65 | Chaparral 2E Chevrolet | Chaparral Cars | white | COX | Firestone | Shell | open | mid |
| 66 | Chaparral 2E Chevrolet | Chaparral Cars | white | COX | Firestone | Shell | open | mid |
| 69 | Hamill SR3 Chevrolet | Hamill Cars, Inc. | white (+blue) | HAMILL SR-3 | Firestone | Valvoline | open | mid |
| 76 | Webster - Oldsmobile | Webster Racing | black/red | | | | open | mid |
| 81 | Lola T70 Mk.2 Chevrolet | Alan Green Chevrolet | dark blue (+light blue) | | Goodyear | | open | mid |
| 83 | Lola T70 Mk.2 Ford | A. J. Foyt Jr. | light blue | | | | open | mid |
| 86 | McLaren Goth Special Chevrolet | Mike Goth Racing | orange | | Firestone | Valvoline | open | mid |
| 88 | McLaren Elva Mark II Chevrolet | Pacesetter Homes, Inc. | dark blue (+green) | Pacesetter HOMES | Goodyear | Valvoline | open | mid |
| 91 | McLaren Elva Mark II Ford | Drummond Racing Organization | silver | | | | open | mid |
| 95 | Nickey Vinegaroon Mk II Oldsmobile | Dan Blocker Motor Racing | white (+purple) | | | | open | mid |
| 96 | McLaren Elva Mark II Chevrolet | Dan Blocker Motor Racing | white/purple | | | | open | mid |
| 97 | McLaren Elva Mark II Chevrolet | Charles Hayes Racing | blue/white | | | | open | mid |
| 98 | Lola T70 Mk.2 Ford | John W. Mecom Jr. | metallic blue (+dark blue/white) | | Firestone | | open | mid |
| 99 | McLaren Elva Mark II Chevrolet | Charles Hayes Racing | blue (+white) | NICKEY Vinegaroon | Goodyear | Valvoline | open | mid |