His family announced the death in a statement. The cause was pneumonia.
In the 1960s, Mr. Gurney was one of the best-known figures in his sport, easily switching from one kind of car to another, equally adept on oval tracks and twisting road courses. He won races by driving stock cars, Indy-style open-wheel cars, sports cars and sleek Formula 1 racers on the European Grand Prix circuit.
As a driver, car designer and team owner, he contributed to several major innovations in motor sports, from rear-mounted engines to aerodynamic devices to the full-face driving helmet.
At 6-foot-3, Mr. Gurney was unusually tall for a driver, and his chiseled, patrician looks sometimes masked his competitive fire. In 1963, Sports Illustrated called him "America's best and most influential racing driver."
He came of age before safety features diminished the dangers of racing, causing him to adopt a detached philosophical approach to his sport, in which many of his friends died in crashes.
"I think about it all the time," he said in 1960. "That's the essence of this, isn't it? To go as fast as you can without getting killed."
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Mr. Gurney became infatuated with speed as a teenage hot rodder racing through the California orange groves. Over time, he was drawn to European-style road racing, which he believed demanded the most skill from a driver. He had an elegant driving style, in which he used his brakes as little as possible.
He won his first Formula 1 race in 1961 and became the first driver with victories in the four major categories of auto racing: Grand Prix, Indy car, NASCAR and sports cars. Only two others, Mario Andretti and Juan Pablo Montoya, have accomplished the feat.
He drove more than 50 kinds of cars, from Ferraris and Fords to Porsches, Brabhams and his own American Eagle brand. According to Motor Age magazine, Mr. Gurney entered 312 races, winning 51 and finishing second or third 47 times.
Among his few disappointments as a driver was his record in the Indianapolis 500, where he came in second in 1968 and 1969 and third in 1970.
One of his greatest triumphs came in June 1967, when Mr. Gurney and his driving partner, A.J. Foyt, won the 24 Hours of Le Mans, often considered the most demanding car race in the world.
Driving a Ford prototype sports car, he and Foyt overpowered the competition, reaching top speeds of more than 200 mph and averaging 135.48 mph for the race — breaking the old record by 10 mph. They traveled 3,220 miles, besting their closest competitor, a Ferrari, by more than 32 miles. It was the first and only time an American driving team won the race in an American-built car.
As the drivers celebrated their victory, Mr. Gurney shook up a bottle of champagne and sprayed its contents on nearby spectators, launching a new tradition.
One week later, on June 18, 1967, Mr. Gurney won the Belgian Grand Prix, driving an American Eagle open-wheel car, which he designed. He averaged more than 145 mph, making it, in the words of Sports Illustrated, "the fastest Grand Prix anywhere, ever, in history."
In January 1968, Mr. Gurney was on his home track in Riverside, Calif., winning the Riverside 500 stock-car race for the fifth time in six years. Driving a Ford Torino, he outran a talented group of drivers that included Andretti, Foyt, David Pearson, Parnelli Jones and Richard Petty.
Mr. Gurney officially retired from driving in 1970 to concentrate on designing cars and organizing racing teams. Cars from his company, All American Racers, won the Indianpolis 500 three times.
Daniel Sexton Gurney was born April 13, 1931, in Port Jefferson, N.Y. His father was a singer with the Metropolitan Opera in New York and sometimes sang the national anthem before his son's races.
Mr. Gurney did not start racing cars until his family moved to California in 1948. He graduated from a junior college, worked as an Army mechanic during the Korean War and began driving competitively in the mid-1950s.
He became an early proponent of rear-mounted engines in the 1960s — now standard for Indy-style and Formula 1 cars. He was among the first drivers to wear a full-face protective helmet and often wore canvas sneakers while racing. He also designed the "Gurney flap," a small projecting lip that makes race cars more aerodynamically stable.
In 1964, Car and Driver magazine touted Mr. Gurney as a mock-serious candidate for president, even though he was then too young for the office.
Mr. Gurney's first marriage, to Arleo Bodie, ended in divorce. Survivors include his wife of 48 years, the former Evi Butz of Newport Beach; four children from his first marriage; two sons from his second marriage; and eight grandchildren.
In 1971, Brock Yates, the editor of Car and Driver, conceived of a renegade coast-to-coast race, the Cannonball Run, named for an early race driver, Erwin "Cannonball" Baker. After an exploratory trip, Yates organized the first full-scale Cannonball Run in November 1971.
Competitors set out from New York City and could drive any kind of wheeled vehicle on any route as fast as they dared.
"The Cannonball had one rule," Yates said. "There were no rules."
The first vehicle to arrive at a seaside hotel in Redondo Beach, Calif., would be declared the winner.
Yates, a part-time race-car driver, had a new Ferrari lined up, but he needed a second driver. Mr. Gurney turned him down at first but called Yates the night before the race.
"I've decided we can't just sit on our fannies anymore," he said, according to a 1972 article Yates wrote for Sports Illustrated. "Everybody's terrified of offending somebody, and I almost got caught in that trap. I'm jumping on the redeye out of Los Angeles right now. I'll meet you just before the start."
With Yates checking maps and watching out for highway patrol officers, Mr. Gurney took the wheel of the Ferrari as they drove westward into the night. A Camaro pulled alongside at 100 mph, challenging Mr. Gurney on the open road.
He punched the accelerator and sped away from the Camaro.
"That's 150, steady as you please," Mr. Gurney said.
Yates drove through parts of the Midwest before Mr. Gurney returned to the wheel to negotiate snow squalls in the mountains of Northern Arizona. He hit a patch of glare ice at 125 mph but kept the car under control.
On a shortcut through a national forest, Mr. Gurney negotiated a 15-mile stretch of downhill switchbacks, set at the edge of sheer cliffs. It was, Yates wrote, perhaps the most impressive display of driving he had ever witnessed:
"I sat there in admiration, watching him run quickly and easily through the nasty turns, never squealing a tire, never wasting a motion on the steering wheel. I had witnessed a virtuoso playing a priceless instrument, and it came to me that this had to be the peak of excellence that every driver must aspire to."
After speeding across the Arizona desert, then negotiating the freeways of Southern California, Mr. Gurney arrived in Redondo Beach 35 hours and 54 minutes after leaving New York. (The record has since been eclipsed.)
He and Yates were awarded first prize — a sculpture made of old wrenches and other tools. Yates later wrote the screenplay for a popular 1981 movie about the race, "The Cannonball Run," starring Burt Reynolds.
Mr. Gurney later explained his decision to drive in the Cannonball to the Los Angeles Times: "I thought, 'What is life all about, anyway?' "
He and Yates were stopped only once for a speeding ticket, when a patrol officer caught up to them at a filling station in Arizona.
After the officer issued the ticket, curiosity got the better of him.
"Just how fast," he asked, "will that thing go?"
"Come on out on the freeway," Mr. Gurney replied, "and we'll let you find out."
He got behind the wheel and hit the road.
"He took his left hand off the wheel and we powered along toward Los Angeles," Yates wrote, "the Ferrari rushing through the desert morning at 172 mph."
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