1978 USAC Championship Car season

The 1978 USAC Championship Car season consisted of 18 races, beginning in Avondale, Arizona on March 18 and concluding at the same location on October 28. The USAC National Champion was Tom Sneva and the Indianapolis 500 winner was Al Unser. This was the last year before the majority of car owners left the USAC to form CART.

By winning the Indianapolis 500, Pocono 500, and California 500, Al Unser swept the Indy car "triple crown," the only driver in history to do so. Sneva became the second driver to win the USAC championship without winning a race during the season, after Tony Bettenhausen in 1958.

Schedule and results
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Final points standings
Note: Janet Guthrie not eligible for points.