1978 USAC Championship Car season
The 1978 USAC Championship Car season consisted of 18 races, beginning at Phoenix 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 first USAC/CART "Split". 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.
The 1978 season is also statistically noteworthy. Danny Ongais won the most races, and Al Unser swept the triple crown races, but it was Tom Sneva who won the championship title. Sneva had six 2nd place finishes, and twelve top 5s, and experienced more consistent finishes. Sneva became the second driver to win the USAC championship without winning a race during the season, the last being Tony Bettenhausen in 1958. Sneva's "winless" championship was not without its critics, however, a statistician calculated points results using contemporary scales of other racing series, and concluded that Sneva would have still won the title in nearly every scenario.
The 1978 season was also a break-out year for future champion Rick Mears. Mario Andretti was running the full Formula One season. Andretti was running a partial Indy car schedule for Penske Racing, and Roger Penske hired the young Mears to fill in for Andretti the weekends he was overseas. Mears, who had spent two years in lesser-funded rides, jumped at the opportunity to drive for Penske, even though it was only a part-time ride. Mears won Co-Rookie of the Year at Indy, won three races, and despite running only 11 of 18 races, finished 9th in points.
Schedule and results
| Rnd | Date | Race Name | Track | Location | Pole Position | Winning Driver |
| 1 | March 18 |  Jimmy Bryan 150 | Phoenix International Raceway | Avondale, Arizona | Danny Ongais | Gordon Johncock |
| 2 | March 26 | Datsun Twin 200 | Ontario Motor Speedway | Ontario, California | Tom Sneva | Danny Ongais |
| 3 | April 15 | Coors 200 | Texas World Speedway | College Station, Texas | Danny Ongais | Danny Ongais |
| 4 | April 23 | Gabriel 200 | Trenton International Speedway | Trenton, New Jersey | Tom Sneva | Gordon Johncock |
| 5 | May 28 | International 500 Mile Sweepstakes | Indianapolis Motor Speedway | Speedway, Indiana | Tom Sneva | Al Unser |
| 6 | June 11 |  Molson Diamond Indy | Mosport Park | Bowmanville, Ontario | Danny Ongais | Danny Ongais |
| 7 | June 18 | Rex Mays Classic | Wisconsin State Fair Park Speedway | West Allis, Wisconsin | Danny Ongais | Rick Mears |
| 8 | June 25 | Schaefer 500 | Pocono International Raceway | Long Pond, Pennsylvania | Danny Ongais | Al Unser |
| 9 | July 16 | Norton Twin 200 | Michigan International Speedway | Brooklyn, Michigan | Tom Sneva | Johnny Rutherford |
| 10 | July 23 | Gould Twin Dixie | Atlanta International Raceway | Hampton, Georgia | Tom Sneva | Rick Mears |
| 11 | August 6 | Texas Grand Prix | Texas World Speedway | College Station, Texas | Tom Sneva | A. J. Foyt |
| 12 | August 20 | Tony Bettenhausen 200 | Wisconsin State Fair Park Speedway | West Allis, Wisconsin | Danny Ongais | Danny Ongais |
| 13 | September 3 | California 500 | Ontario Motor Speedway | Ontario, California | Tom Sneva | Al Unser |
| 14 | September 16 | Gould Grand Prix | Michigan International Speedway | Brooklyn, Michigan | Johnny Rutherford | Danny Ongais |
| 15 | September 23 | Machinist Union 150 | Trenton International Speedway | Trenton, New Jersey | A. J. Foyt | Mario Andretti |
| 16 | October 1 |  Daily Empress Indy Silverstone | Silverstone Circuit | Silverstone, England | Danny Ongais | A. J. Foyt |
| 17 | October 7 | Daily Mail Indy Trophy | Brands Hatch | Fawkham, England | Al Unser | Rick Mears |
| 18 | October 29 | Miller High Life Bobby Ball Memorial 150 | Phoenix International Raceway | Avondale, Arizona | Danny Ongais | Johnny Rutherford |