1979 California 500

The 1979 California 500, the tenth running of the event, was held at the Ontario Motor Speedway in Ontario, California, on Sunday, September 2, 1979. The event was race number 11 of 14 in the 1979 SCCA/CART Indy Car Series. The race was won by Bobby Unser, his third California 500 victory. It was the first year of the California 500 under CART sanctioning.

In late 1978, the CART series was formed as a collective of race teams who formed a sanctioning body to address problems they faced in auto racing, ones they felt were ignored by USAC. While some events switched allegiance to CART, the Triple Crown of 500 mile races comprising Indianapolis, Pocono, and Ontario maintained loyalty to USAC.

On March 25, USAC opened their season at Ontario with a 200-mile doubleheader of Indy cars and USAC Stock Cars. A. J. Foyt won both races. CART teams skipped the event and Foyt had no real challengers. The event attracted what was described as the smallest crowd in track history at around 20,000.

On April 19, 1979, the USAC board of directors voted unanimously to reject the entries for the 1979 Indianapolis 500 of six key teams: Penske, Patrick, McLaren, Fletcher, Chaparral, and Gurney. These six teams (19 cars) were alleged to be "harmful to racing" and "not in good standing with USAC." USAC sent the owners a telegram informing them of the situation while they were participating in the CART race at Atlanta, the Gould Twin Dixie 125s.

On April 26, the "rejected six" teams filed suit in the U.S. District Court for the Southern District of Indiana, requesting an injunction to allow the teams to compete in the 1979 Indy 500. They cited antitrust and restraint of trade. On May 5, judge James Ellsworth Noland issued the injunction, but restrained the teams from disrupting or interfering with the running of the event. Rick Mears won the Indianapolis 500 for Team Penske.

On June 1, the Indianapolis Motor Speedway declared that the 1980 Indianapolis 500 would be invitation only. In order to receive an automatic invitation, teams would have to run at Pocono on June 24 and Ontario on September 2. The move also protected the Speedway legally from disallowing entries.

CART declared they would boycott all remaining races sanctioned by USAC. They openly suggested they could run a 500 kilometer race at Trenton Speedway on the same day as Pocono and would honor Pocono tickets.

Seeing how the conflict was hurting Indy Car racing, both sides approached Ray Smartis, General Manager of Ontario, to lead peace talks in early June. As a result of the talks, CART dropped their plans to rival the Pocono 500 "in a good faith move in the best interest of auto racing." Smartis presented peace plans for a unified Indy car series to USAC who rejected the idea.