Oldsmobile and Chevrolet pioneered the technology for mass-market cars, but the turbos flopped — and took decades to gain acceptance.
By guest author Roy Furchgott from the New York Times
In 1962, rival divisions inside General Motors — Oldsmobile and Chevrolet — concluded a furious intramural race to build an advanced engine using battle-proven technology used in World War II fighter planes. This technology boosted both engine power and gas mileage. It also pointed the way for Detroit to break its addiction to ever larger gas-guzzling engines by getting more power from lighter, more efficient motors.
That cutting-edge technology was called a turbocharger. In the 1960s it was exotic, it was innovative, and for G.M. it was — above all — a disaster.
The Olds F-85 Jetfire and the Chevy Corvair Monza Spyder were America’s first mass-produced turbocharged passenger cars, and they were such technological and commercial flops that Detroit would shun turbos for years to come.
The turbo, now found on everything from Honda Civics to BMW’s Z4 M40i Roadster, would not gain mass acceptance until the 1980s, when its reputation was restored by a quirky Swede.
Not even the General Motors Heritage Center’s archives — with enough documents to stuff a file drawer nearly three miles long — hint at why not one but two turbocharger projects were greenlighted in the late 1950s. While carmakers then were engaged in a horsepower arms race, gas was cheap and Detroit’s maxim was: “There is no replacement for displacement.”
But it was also the dawning of the Space Age, when people were awed by the promise of technology. G.M.’s innovation leader had been Oldsmobile. But in 1956 the iconoclastic Ed Cole, whose motto was “Kick the hell out of the status quo,” became Chevy’s general manager, and he began kicking with, among other things, the Corvair. A competition ensued.
Turbos weren’t unknown. They appeared in the early 1900s and, by World War II, were on American warbirds like the B-24 Liberator, the P-38 Lightning and P-47 Thunderbolt. After the war, diesel trucks used them.
The concept of turbocharging is easy to understand. The turbo uses the exhaust gases from an engine to spin a tiny turbine, which in turn spins a second turbine. That second turbine sends a pressurised, concentrated mix of fuel and air into the cylinders for a more power-packed charge. It also burns more completely, which increases fuel efficiency.
But more engine power means more heat. That isn’t a problem for diesel engines, which are less finicky and burn cooler than gas engines, said Brandon Stevenson, who teaches advanced vehicle systems at Weber State University.
“Gas engines,” he said, “when it comes to the air fuel mix, are not as forgiving as a diesel engine.” Which both Olds and Chevy would discover.
The two divisions undertook the production of the turbo independently, and probably unknown to each other, at least initially.
General Motors divisions commonly worked in secrecy. The Corvair was disguised as a project for Holden, G.M.’s Australian subsidiary. “We got Holden drafting paper, Holden stationery, Holden purchase orders — the whole shot,” recalled a former senior project engineer, Robert Benzinger, in a 1975 speech to the Corvair Society of America.
Even without a turbo, heat was a challenge for the Corvair’s air-cooled aluminum engine. But the issue intensified with turbocharging.
“The full output of the engine cannot be cooled!” Mr. Benzinger exclaimed. Chevy assumed “the driver would either run out of road or run out of guts before the engine overheated,” he added.
In tests, the turbo engine burned holes through the valves. The engine needed a belt-driven cooling fan, but belts failed at top revolutions per minute, owing to the weight of the fan. So Chevy worked with DuPont to make a lighter fan from a promising new plastic, Delrin, which caused an even worse problem.
After a trip from Detroit to Ohio, a test driver told Mr. Benzinger that as he accelerated from a tollbooth, “I started to choke, and my eyes started burning.”
A frantic search for the cause was begun, leading to a convoy of four Corvairs retracing the route, each with one engineer from Chevrolet and one from DuPont. Theories varied, postulating a problem with Toledo air or static electricity generated by the fan. They drove the route radioing back and forth, “Smell anything yet?”
In the Ohio cold, with the heater on full blast, so much current ran through the battery in the hot engine compartment that it essentially boiled. Vaporized battery acid reacted with the Delrin to make formaldehyde gas, which flooded the cabin. The potential casualties, Mr. Benzinger said, caused him to “shudder to this day.” A cast aluminum fan was substituted.
The death of the Corvair was due not to the turbo but to Ralph Nader. His 1965 book, “Unsafe at Any Speed,” painted the Corvair as a deathtrap, ushered in an era of consumer activism and led to the founding of the National Highway Traffic Safety Administration. That agency later absolved the Corvair in a 140-page report, calling its handling “at least as good as the performance of some contemporary vehicles both foreign and domestic.”
Accounts of the Jetfire development are not as common, complete or colorful, but major problems appeared after the car was sold.
“It came out of their Olds experimental division,” said Jim Noel, a hobbyist who at 80 has most likely rebuilt more Jetfire turbochargers than anyone alive. Oldsmobile borrowed from the aircraft’s approach to the cooling problem, with “water injection.”
The air inlet was cooled by a mist of water and alcohol, increasing boost and reducing heat and other accompanying ignition problems.
Olds fancifully called the water and alcohol mix Turbo-Rocket Fluid, which was in a separate five-quart tank. “If you were hot-rodding around, you could go through a tank of fluid in a week or two,” Mr. Noel said. Then people didn’t refill the tank.
But it got worse. The alcohol mix made hoses and diaphragms brittle. A poorly designed seal let gunk build up and seize the turbine. The turbo-rocket reservoir remained pressurized when the car was off, and it could partly fill the cylinders with fluid, potentially breaking rods and pistons on restart.
Worst of all, Mr. Noel said, “the lawyers got involved and wanted safety devices.” Those devices crippled the turbocharger often enough to render it largely useless.
Oldsmobile offered Jetfire owners the option of removing the turbo. In 1985, when Mr. Noel was introduced to two Oldsmobile employees who had worked on the Jetfire, he was told that “of the 9,607 Jetfires produced, about 80 % had the turbo taken off and replaced with the four-barrel.”
Both Jetfire and Corvair camps claim their brand was first with the turbocharger, which would seem a Pyrrhic victory. Oldsmobile was announced first, but the Monza Spyder was publicly shown first, which obscures the larger point: First or second, these cars tainted turbo technology. Until the Buicks of the ’80s, “G.M. didn’t touch another turbo,” Mr. Noel said.
After G.M.’s failures, turbos were seldom seen except on trucks, racecars and limited-production performance cars.
That changed in 1979 when Robert Sinclair became president of Saab Cars USA. An affable but hard-charging executive whom Saab aficionados call “Uncle Bob,” Mr. Sinclair had a sales and marketing background that led him to challenge Saab’s business strategy.
“‘You guys appear set on building something akin to a stripped-down Scandinavian Volkswagen. What I’m interested in selling is a high-performance Swedish four-passenger Porsche,’” he recalled telling the board, in a 2006 interview with Hemmings Sports and Exotics. “We were the only company who had turbos in a standard production car, and the cars had such immense possibilities.”
In 1978, the Saab 99 had offered the first turbo on a production car since G.M.’s misfires. “The very first Saab turbos were not reliable cars,” said Jim Smart, owner of the Saab specialist Smart Motors in Santa Fe, N.M. “To make it work really well needed advanced engine management.”
Nevertheless, the automotive press raved. “It comes as something of a shock to all of us to discover that safe, sane, snow-proof Saab now has fetched up a model that’ll get second-gear rubber,” Patrick Bedard wrote in Car and Driver. “Who knows? Maybe the law of gravity will be repealed next.”
In 1982, Saab’s turbos added its breakthrough Automatic Performance Control, a microphone that listened to engine combustion and made adjustments on the fly. The engine became functional, reliable and economical. The word turbo became synonymous with Saab.
But Saab’s crowning achievement came in 1983, when the company forced a stripped two-door notchback on Saab USA. Mr. Sinclair required upgrades like cast wheels, a premium sound system and leather upholstery.
“I got down to the end of the list,” he recalled in that 2006 interview, “and said, ‘Oh, yes, there’s one more item.’ ‘What’s that?’ ‘A convertible top.’”
The convertible, one of few available, hit showrooms in 1986. With America still feeling the effects of the 1970s oil crisis, a convertible with a peppy, fuel-efficient turbo engine was a smash hit. A quarter of a million Saab convertibles were sold over 20 years.
The Saab made the turbo more than acceptable; it was prestigious. Owners who didn’t have a turbo on their Saab wanted people to think they did. “A guy I knew who worked in Saab parts said he sold more turbo badges than cars,” Mr. Smart said.
With technical and image problems quashed, turbos crept back. By the mid-1980s they could be found on a Volvo wagon, the Porsche 944, the Ford Mustang SVO, the Datsun 280ZX, the Dodge Daytona Shelby Z and Chrysler’s LeBaron GTS.
By the 2020 model year, 35 % of new vehicles were turbocharged, according to an Environmental Protection Agency report.
When the 1962 brochure for the F-85 Jetfire called its engine “revolutionary,” it was right. It was just 16 years too early.