1958 United States Grand Prix for Sports Cars
The 1958 United States Grand Prix for Sports Cars was a sports car race held at Riverside International Raceway on October 12, 1958. It was the fourth and final round of the 1958 USAC Road Racing Championship season, the seventeenth round of the Sports Car Club of America's Pacific Coast Championship, the second running of the Riverside Grand Prix, and the first post-World War II running of the United States Grand Prix. The race was held over 62 laps of Riverside's circuit, for a total of. Chuck Daigh won the race overall, driving one of Lance Reventlow's Scarab-Chevrolets. The race is also noteworthy in the annals of international racing, as the strong second-place finish by a local driver named Dan Gurney earned him a test drive in a factory Ferrari Formula 1 car, effectively launching the Californian's legendary racing career.
The weather at this event was very warm, even for a desert climate that routinely saw daytime temperatures of 100F plus during the summer. On race day the temperature reached an extraordinary high for the era ; with winds gusting up to on race day. Even with the global warming that emerged decades after the late 1950s, the maximum temperature of Riverside, California never exceeded for the month of October 2013.
Entry
The race was open to cars meeting the Sports Car Club of America's B Modified through G Modified classes. Although named "modified", most of the cars in classes C through G were factory-built sports racing cars. The field was unusually large for an American sports car race, attracted in large part by a large purse consisting of $14,500.Qualifying
Pole position winners in each class are marked in bold.| Pos | Class | Car | Driver | Lap Time |
| 1 | BM | #5 Scarab Mk II-Chevrolet | Chuck Daigh | 02:04.0 |
| 2 | CM | #2 Ferrari 412 S | Phil Hill | 02:06.0 |
| 3 | BM | #3 Scarab Mk II-Chevrolet | Lance Reventlow | 02:08.1 |
| 4 | CM | #59 Aston Martin DBR2 | Bob Oker | 02:09.7 |
| 5 | CM | #69 Ferrari 375 Plus | Dan Gurney | 02:10.2 |
| 6 | CM | #11 Ferrari 335 S | John von Neumann | 02:10.8 |
| 7 | BM | #70 Ol' Yaller Mk.I-Buick | Max Balchowsky | 02:11.1 |
| 8 | DM | #159 Aston Martin DBR1 | Roy Salvadori | 02:11.6 |
| 9 | DM | #211 Ferrari 250 TR | Richie Ginther | 02:12.3 |
| 10 | BM | #172 Kurtis 500X-Cadillac | Jerry Unser | 02:12.4 |
| 11 | CM | #27 Jaguar D-Type | Bill Krause | 02:13.6 |
| 12 | BM | #111 Devin-Chevrolet Special | Ak Miller | 02:13.7 |
| 13 | FM | #7 Porsche 718 RSK | Jean Behra | 02:14.3 |
| 14 | BM | #14 Lister-Corvette | Bill Pollack | 02:15.5 |
| 15 | CM | #88 Ferrari 410 S | Masten Gregory | 02:15.6 |
| 16 | CM | #78 Maserati 450S | Carroll Shelby | 02:15.6 |
| 17 | BM | #229 Chevrolet Special | Clem Proctor | 02:17.6 |
| 18 | BM | #264 Huffaker Special-Chrysler | Fred Knoop | 02:17.7 |
| 19 | EM | #50 Porsche 550 RS Spyder | Ken Miles | 02:18.0 |
| 20 | FM | #126 Lotus Eleven | Pat Pigott | 02:18.6 |
| 21 | EM | #155 Ferrari 500 TR | Sam Weiss | 02:18.8 |
| 22 | BM | #149 Zidar Special | Ray Crawford | 02:19.8 |
| 23 | GM | #125 Lotus Eleven | Pete Lovely | 02:21.8 |
| 24 | BM | #98 Maserati 450S-Pontiac | Jim Rathmann | 02:22.9 |
| 25 | GM | #127 Lotus Eleven-Climax | Skip Conklin | 02:23.4 |
| 26 | EM | #9 Meyer-Drake Special-Offenhauser | Bill Cantrell | 02:24.0 |
| 27 | FM | #49 Cooper-Climax | Bob Drake | 02:24.3 |
| 28 | FM | #117 Osca TN | Harry Hanford | 02:24.4 |
| 29 | FM | #4 Lotus Eleven | Lew Florence | 02:24.6 |
| 30 | EM | #135 Ferrari 500 TR | Alan Markelson | 02:24.9 |
| 31 | CM | #129 HWM-Chevrolet | Ralph Ormsbee | 02:25.3 |
| 32 | BM | #96 Kurtis-Ford | Marvin Porter | 02:25.4 |
| 33 | BM | #110 Caballo de Hiero Mk II-Oldsmobile | Bobby Unser | 02:26.3 |
| 34 | EM | #121 Ferrari 500 TRC | Frank Becker | 02:26.3 |
| 35 | BM | #93 Buick Special | Floyd Burt | 02:27.6 |
| 36 | FM | #122 Cooper-Porsche | Tom Meehan | 02:28.2 |
| 37 | FM | #124 Porsche 550 RS Spyder | George Keck | 02:28.3 |
| 38 | DM | #259 Aston Martin DB3S | William de Creeft | 02:28.8 |
| 39 | EM | #35 Osca 2000 | Pearce Woods | 02:29.0 |
| 40 | BM | #140 Kurtis-Buick | Bill Cheesbourg | 02:30.1 |
| 41 | EM | #23 Lotus Mark X | John Timanus | 02:30.4 |
| 42 | DM | #118 Porsche 356 Carrera GT Coupe | Jean Pierre Kunstle | 02:34.2 |
| 43 | DM | #138 Duncan Special | Bill Love | 02:35.3 |
| 44 | EM | #26 Ferrari 500 TR | Gordon Glyer | 02:36.5 |
| 45 | BM | #6 Kurtis-Buick | Troy Ruttman | no time |
| 46 | BM | #181 Mercedes-Benz 300 SL-Corvette | Johnnie Parsons | no time |
| DNQ | FM | #8 Maserati 150S | Dusty Miller | – |
| DNQ | BM | #16 Scarab Mk I-Chevrolet | Lance Reventlow | – |
| DNQ | BM | #52 Kurtis-Corvette | Bert Ruttman | – |
| DNQ | CM | #77 Ferrari 735 LM | Rodger Ward | – |
| DNQ | EM | #114 Sebring 2000SS | Hank Tubman | – |
Race result
Class winners marked in bold.| Pos | Class | No | Team | Drivers | Car | Laps |
| 1 | BM | 5 | Reventlow Automobile Incorporated |  Support racesTwo support races were held: a production car race won by Skip Hudson in a Chevrolet Corvette, and an under-1400cc race won by Jock Ross in a Cooper-Climax. |