The 1970 California 500, the inaugural running of the event, was held at the Ontario Motor Speedway in Ontario, California, on Sunday, September 6, 1970. The event was race number 12 of 18 in the 1970 USAC Championship Car season. The race was won by Jim McElreath, his final Indy Car victory. The race commenced an 11-year history of the California 500 being a part of IndyCar racing's Triple Crown.
Background
Plans for Ontario Motor Speedway were announced on February 16, 1966. Its primary financial backers were the Stolte Construction Company and Filmways Inc., a film production company that produced television shows such as The Beverly Hillbillies, Petticoat Junction, Green Acres, and The Addams Family. Upon the announcement, USAC agreed to sanction a pair of 500-mile races for Indy cars and stock cars. The inaugural race was scheduled for December 1, 1968.
Advertised as the "Indianapolis of the West", the track was similar in design to the Indianapolis Motor Speedway as a 2.5-mile oval with four distinct turns. In addition, the track would feature a 3.1-mile road course in the infield and a quarter-mile drag strip on the frontstretch. The track would have seating for over 150,000 spectators, standing room for 100,000 additional people, parking for 68,000 cars, and a control tower in the infield that stood 14 stories high.
The economy and bond market slowed in mid-1966 when funding was being raised, leading to delays in construction. Filmways withdrew from the project. In early 1967, Ontario informed USAC that construction would not be completed by the December 1968 target date. USAC responded by holding races at the nearby Riverside International Raceway between 1967 and 1969.
Once funding was secured through the selling of bonds, groundbreaking on the track officially took place on September 25, 1968. Dignitaries attending the ceremony included local officials and actor Kirk Douglas. Construction costs were anticipated to cost $25.5 million.
In 1969, USAC announced the California 500 would be held on the Sunday of Labor Day weekend for the next 10 years, beginning on September 6, 1970. USAC President, Charlie Brockman, declared "Ontario Motor Speedway is the most exciting and promising development in automobile racing since Tony Hulman bought the Indianapolis Speedway in 1946."
In May 1970, Al Unser won the Indianapolis 500.
Opening ceremonies for the track occurred on Sunday, August 9, 1970. Exhibitions of drag racing, stock car racing, and Indy car racing were done, followed by a Pro-Am celebrity race. Celebrities were teamed with pro drivers in new Porsches, with the pro driving three laps, the celebrity driving three laps, the pro again driving three laps, and the celebrities driving the final three laps. Professional drivers included Bobby Unser, Dan Gurney, Al Unser, Parnelli Jones, Mario Andretti, and Mark Donohue. Celebrities included Dick Smothers, Hugh Downs, Pancho Gonzalez, Paul Newman, James Garner, Pete Conrad, Dino Martin, and Ken Venturi. Unser and Smothers teamed to win the race followed by Donohue and Conrad.
Practice and Time Trials
Practice for the California 500 officially opened on Saturday, August 22. 27,852 spectators attended the practice session, attracted by free admission. Only seven cars made practice runs. Mark Donohue posted the fastest speed at 165.14 mph. The six-hour practice session was delayed over an hour due to faulty caution lights on the backstretch. Kevin Bartlett was the first driver to go on track when practice began. Bartlett was also responsible for the only incident of the day when he spun in turn one but avoided any damage.
Donohue upped his speed to 169.81 mph on day two. On Monday, Donohue posted a speed of 171.4 mph. On Tuesday, the Vel's Parnelli Jones Racing teammates of Joe Leonard and Al Unser began practicing. Leonard posted the fastest speed at 172.41 mph. Practice ended one hour early as a dust storm covered the track.
On Wednesday, Leonard ran a speed of 175.10 mph. At speed, Mario Andretti's car lost a nose cone on the frontstretch. "It just popped off and flew right over my head. Otherwise it was no problem." For the second straight day, practice ended an hour early due to dust storms.
Leonard upped his speed to 177.2 mph on Thursday. Unser was second at 175.8 mph, followed by Johnny Rutherford at 175.4 mph. The first crash at the track occurred when Greg Weld spun in turn two and hit the wall broadside. The car was repaired. A $1 million lawsuit filed by George Follmer against USAC was settled. Follmer had been suspended for running two unauthorized Trans-Am races but was allowed to begin practicing on Friday.