Each of these inaugural races drew attendance second only to their established counterparts, the USAC Indianapolis 500, the NASCAR Daytona 500, the NHRA U.S. Nationals, and the U.S.

The track was purchased for real estate development by Chevron Land Company in late 1980[5] and demolished at a cost of $3 million in 1981.

The second attempt focused on an 800-acre parcel of land (the Cucamonga Winery) directly across from the new Ontario International Airport on the San Bernardino Freeway (Interstate 10), 40 miles (60 km) east of downtown Los Angeles.

William Loorz CEO of Stolte Construction Co., one of California's largest commercial construction companies, who had been designated the contractor on the project, sent information on the failed projects to David Lockton, co-founder with Chuck Barnes of Sports Headliners, a leading sports management firm in Indianapolis, Indiana, that acted as agent and manager for most of the Formula One and Indianapolis-style racing drivers.

He flew to Los Angeles in October 1966, met with Stolte and viewed the proposed site which had by then been subdivided into fourteen separate parcels owned by 150 individual owners, many of them Hollywood celebrities who had bought the land for tax shelters.

He obtained the first and only IRS ruling to allow tax deductibility of the $25.5 million industrial revenue bond offering secured by the real estate, in which the facility would be run by a for-profit operating company.

He also raised $5 million in equity from Pioneer Lands Corp.; Donaldson, Lufkin & Jenrette; and Stolte Construction Company; with Lockton and these three entities owning the speedway in more or less equal proportions.

The racing surface was one lane wider and, unlike the Indy speedway, the short chutes (the two shorter straight-aways, at either end of the track) were banked, which made the OMS slightly faster.

The research indicated that in order to attract more than the approximately 50,000 hardcore racing fans in Southern California it would be necessary to convince the non-racing fan of the new speedway's safety to overcome their fears of seeing a terrible accident; to position the facility as a clean, safe, fun place to take the family, and a place to rub elbows with Hollywood stars, astronauts and other celebrities.

The speedway launched a radio, billboard and newspaper advertising campaign, developed by the Los Angeles-based Campbell Ewald Agency, in December 1969, promoting the California 500 as "the place for the family to be for their Labor Day weekend" nine months later.

The speedway's board of directors when the track opened consisted of chairman Dan Lufkin, of Donaldson, Lufkin, Jenrette; CEO David Lockton; Donald Riehl, of DLJ; William Loorz, CEO of Stolte Construction; Paul Newman, Kirk Douglas, and Dick Smothers from the entertainment industry; J.C. Agajanian, an American motor sport promoter and race car owner; Parnelli Jones, 1963 winner of the Indianapolis 500; Roger Penske, retired race car driver, race car owner and auto related business entrepreneur; Briggs Cunningham, an American sportsman who raced cars and yachts; and Chuck Barnes, chairman and CEO of Sports Headliners, and former director of public relations for Firestone Tires.

California governor Ronald Reagan presented the trophy to race winner Jim McElreath, a teammate of car owner A. J. Foyt.

The Questor Grand Prix, won by Mario Andretti on March 28, 1971, was a head-to-head battle between European drivers using Formula One cars against the U.S.

The crowd of only 55,000, while the largest to attend a road race in California, was a disappointment; even so, the speedway's schedule of upcoming events printed on page 130 of the 1971 California 500 official program listed a "Second Annual Questor Grand Prix" taking place on April 9 as "One of two full-points World Championship Formula 1 races scheduled for the U.S. next year."

Despite the speedway's commercial success in building attendance for each event and the clear potential for future profitability, in the short term, the operating company had difficulty meeting its debt service obligations on the municipal bonds, primarily due to the shortfall of the hybrid Questor Grand Prix race and a downturn in California 500 attendance in year two.

Rather than a sustained campaign, the advertising or promotional money was not spent on the 1972 race until only a few weeks before the event and attendance was marginally down approximately 30,000 in the second year.

The March crowds never approached the attendance of the Labor Day event and the new operator ultimately defaulted on the debt service.

[6][7] Ontario was used in a number of TV shows and movies, including Salvage One, Charlie's Angels, Death Race 2000 and was also mentioned in CHiPs.

Performers included Ted Nugent, Aerosmith, Santana, Dave Mason, Foreigner, Heart, Bob Welch, Stevie Nicks and Mick Fleetwood, Mahogany Rush and Rubicon.

The fastest lap on the original 3.194-mile Road Course is 1:41.257, set by Jackie Stewart in a Tyrrell 001, during qualifying for the 1971 Questor Grand Prix.