1979 Indianapolis 500

The 63rd 500 Mile International Sweepstakes was held at the Indianapolis Motor Speedway in Speedway, Indiana, on Sunday May 27, 1979. Brothers Al and Bobby Unser combined to lead 174 of the 200 laps, but Al dropped out around the midpoint, and Bobby slipped to 5th place at the finish nursing mechanical issues. Al was driving Jim Hall's radically new Chaparral 2K ground effect chassis in its Indy debut. The car would be victorious the following year with Johnny Rutherford behind the wheel. Second-year driver Rick Mears took the lead for the final time with 18 laps to go, and won his first Indianapolis 500. Mears would win again in 1984, 1988, and 1991, to become the third driver (along with A. J. Foyt, Al Unser Sr., and later Hélio Castroneves) to win the Indy 500 a record four times. It was also Mears' first of a record six Indy 500 pole positions, a mark that still stands as of 2025.

The month of May 1979 was filled with controversy on and off the track. The race was sanctioned by USAC, and was part of the 1979 USAC National Championship. USAC had sanctioned the Indianapolis 500 and the sport of Indy car racing since 1956. During the offseason, however, several teams broke off and formed Championship Auto Racing Teams (CART), a new sanctioning body and new series for Indy cars. It was the beginning of the first open-wheel "split". For 1979, there would be two competing Indy car championships. Many participants took part in the inaugural 1979 SCCA/CART Indy Car Series, skipped the other USAC-sanctioned events, and entered the Indy 500 only as a one-off. USAC responded by rejecting the entries of several top CART-based teams. The owners immediately filed suit, and a court injunction was issued to allow them to participate. Technical squabbles also confounded the month. USAC had re-tooled the turbocharger boost rules, which drew the ire of some crews. During time trials, several cars were disqualified due to illegal wastegate exhaust pipes. Qualifying closed with the traditional 33 cars in the field. However, the day before the race a special qualifying session was arranged to allow certain entries a last chance to qualify. Two additional cars were added to the field, for a total of 35 cars (the most since 1933).

The high tensions and technical squabbles during the month attracted considerable negative criticism from sports writers and media. The race itself, however, was competitive and entertaining, and completed without major incident or further controversy.

Among those in attendance was former president Gerald Ford. Ford also served as the grand marshal of the 500 Festival Parade. The 1979 race is also notable in that it was the first to utilize the "pack-up" rule during caution periods, eliminating the then-primitive virtual safety car rules ("Electro-PACER") used from 1972 to 1978. On the onset of a caution period, the pace car would now pick up the leader and lead the field under the yellow flag at reduced speed. The remainder of the cars would "pack-up" or "bunch up" behind the leader.

Following the 1978 race, and after other superspeedway races that summer including Pocono and Ontario, competitors began complaining about the horsepower advantage that the newer V-8 engines (namely the Cosworth DFX) had over the venerable 4-cylinder Offenhauser engines. USAC held special meetings in August and September of that year to draft new turbocharger boost rules and engine regulations in an effort to establish an equivalency formula. In September, they released a series of preliminary rule changes for the 1979 season. All turbocharged engines would be permitted 80 inHg of boost, and pop-off valves would now be required during practice, qualifying, and during the race. Previously, pop-off valves were only affixed to the turbocharging system during official qualifications. The fuel allotment for 500-miles races was increased to 333 gallons (up from 280) of methanol, and rear wings were reduced from 43 inches to 36 inches. The increase in fuel allotment would reduce the necessary fuel mileage for the 500 miles to 1.5 miles per gallon.

In January 1979, however, another meeting was held to iron out an equivalency formula. USAC met with several owners/chief mechanics including Smokey Yunick, Mike Devin, Bill Finley, Pat Patrick, as well as Cosworth founder Keith Duckworth. The rules were changed once again, though the competitors left the meeting claiming that USAC mostly ignored their technical input. The 161.7 cubic inches (2.650 L) turbocharged V-8 engines were reduced to only 50 inHG of "boost", while the 4-cylinder Offys would be permitted 55 inHG. Additionally, the 209.3 cubic inches (3.430 L) stock block engines were allowed 58 inHG. Normally aspirated engines were allowed a 219 cubic inches (3.59 L) displacement, but few were expected to be entered. By the month of May, USAC had once again tweaked the rules, upping the Offenhauser's boost to 60 inHG, but keeping the V-8s at 50 inHg. With the lower boost levels overall, the increased fuel allotment rule was scrapped. Cars were again limited to 280 gallons of methanol for the 500 miles, which required an average of 1.8 miles per gallon to finish the race.

Following the death of Indianapolis Motor Speedway president Tony Hulman in 1977, owners and participants in Indy car racing were anxious to reorganize the sport. By 1978, a growing dissent amongst the participants was based on many factors, including poor promotion and low revenue. Indy Car events outside of the Indianapolis 500 were suffering from poor attendance, and few events were even televised. Robin Miller even accused the Speedway of offering a purse that was too low considering the stature of the event and the costs of racing at the time. Further complicating the issue were rumors that Goodyear was considering pulling out of the sport. In addition, the venerable 4-cylinder turbo Offenhauser (a favorite of the USAC-loyal teams) was at a horsepower disadvantage to the new V8 Cosworth DFX. USAC began retooling turbocharger boost rules to ensure the Offy and the "stock block" engines remained competitive, which caused new disagreements about equivalency formulas and favoritism. Further driving dissent was the fact that USAC had lost several top officials in a tragic 1978 plane crash.

Driver, owner, and advocate Dan Gurney published a white paper lobbying several complaints and charges against USAC and IMS, concluding that a new organization was necessary to ensure the success of Indy car racing into the future. In late 1978, several existing Indy car owners broke off and created the Championship Auto Racing Teams (CART) series with some initial assistance from the Sports Car Club of America (in order to be recognized by Automobile Competition Committee for the United States). The seed of dissent had been growing for several years before the accident, and claims the crash was an immediate cause for the 1979 USAC/CART "split" are considered for the most part unfounded.^{[citation needed]}