Garretten Greddy'ye: The Turbo Revolution's Journey Through Racing and the Streets

A turbocharger is a mechanical device that recovers the energy of exhaust gas and compresses more air into the engine; it received its first patent in 1905 and, after passing through the race tracks, has today become the backbone of mass-produced automobiles. On this page, you will follow the story on a single timeline, extending from the first truck application in 1938 and the first production cars of 1962, to Porsche's 1,000-horsepower Can-Am monsters, Formula 1's turbo era, and the rise of small-displacement turbo engines after the oil crisis.

The history of the turbocharger: an idea born from the exhaust

The basic logic of the turbocharger is simple and, from an engineering standpoint, very elegant: the exhaust gas expelled from the engine already carries energy; turning that energy with a turbine and using a compressor on the same shaft to compress the intake air. Unlike a supercharger, this power comes not from the engine's crankshaft, but mostly from exhaust flow that would otherwise go to waste. The idea was formalized with the first patent dated 1905, but it took more than four decades to reach the automobile.

The first commercial vehicle application took place in a road vehicle: Swiss manufacturer Saurer introduced a turbocharged truck engine in 1938. Turbo diesel road trucks were appearing in Europe on the eve of World War II, while wartime aviation matured the technology. Turbocharged military aircraft such as the P-38, B-17, and P-47 could maintain performance at high altitudes by using exhaust energy, unlike mechanically driven superchargers.

1962: The first turbocharged production cars on the road

The turbocharger's first encounter with mass-produced cars happened in the same model year in two different GM products: the Chevrolet Corvair Monza Spyder and the Oldsmobile Jetfire. Oldsmobile took its 215 cubic-inch V8 from 155 hp to 215 hp with a turbo; Chevrolet raised its 145 cubic-inch flat-six from 98 to 150 hp. Both systems ran at around 5 psi of boost with a carbureted "draw-through" setup - extremely modest by today's standards, but a groundbreaking power increase for the time.

The Jetfire's road was shorter. To control detonation, which was inevitable in low-compression-ratio engines, the model required a methanol-water injection system called Turbo-Rocket fluid, and after two model years it was discontinued with a production run of roughly 9,600 units. The Corvair, on the other hand, sold for five years, sold more than 50,000 units, and the option was dropped at the end of the 1966 model year. In short, the turbocharger was, on its first attempt, a technologically sound but commercially premature idea.

Turbo on the race track: From the Indy 500 to the Can-Am giants

Turbocharging entered motorsport before series production. In 1952, Cummins' Kurtis Kraft special with a 6.4-liter turbodiesel engine took pole position at the Indy 500 with Fred Agabashian; but the car dropped out of the race after the air filter swallowed track debris. The real explosion began in 1966 with the appearance of the first turbocharged Offenhauser on the grid; in 1968, Bobby Unser won the Indy 500 with the turbo-Offy, and these engines could produce 1,200 hp with 54 psi of boost in qualifying. After the fatal accidents of 1973, boost was limited to ~39 psi.

Porsche 917/10 and 917/30: 1,500 horsepower from the exhaust

Porsche could not continue with the 917's 4.5-liter engine because of the 3-liter engine rule. Under Ferdinand Piëch's leadership, the team led by Hans Mezger and Valentin Schäffer raised the engine to 1,000 PS (735 kW) with twin exhaust turbochargers. On July 30, 1971, Jo Siffert drove the turbocharged 917/10 for the first time at Hockenheimring. The later 917/30, with its 5.4-liter twin-turbo flat-12, produced more than 1,500 hp in qualifying, with boost rising to 32 psi. Mark Donohue won 6 of 8 races in the 1973 Can-Am season; in 1975 at Talladega, he set a lap record of 221,160 mph. This car, which also featured driver-controlled boost adjustment, showed the most radical face of turbo lag - the 1972 version's throttle response was described as like an "on-off switch."

Formula 1's turbo era: From 1977 to 1988

Renault's RS01 started Formula 1's turbo era at Silverstone in 1977. Taking to the track with a single turbo and 500 hp, the car was mocked by rivals as the "yellow teapot." The scorn did not last long: In 1979, the RS10 brought twin turbochargers and an intercooler, and Jean-Pierre Jabouille's victory at Dijon made the turbo a serious option. By 1983, BMW, Honda, Renault, Alfa Romeo, Hart and TAG/Porsche were supplying turbo engines; in qualifying, 45 psi of boost and 700 hp were being talked about. In 1985, 5.5 bar (~82 psi) of boost and an estimated 1,500 hp - 1,000 horsepower per liter, in 1,200-pound cars.

The finale of the era was a show: In 1988, with the McLaren MP4/4 and the Honda RA168E twin-turbo V6, Senna and Prost won 15 of the 16 races. The FIA banned turbo engines from the 1989 season onward; that is why some calendars close the era in 1988 and others in 1989 - in practice, the difference is a one-season shift between the year the last cars raced and the year the ban took effect.

The descent into road cars: The difficult rise of the '70s and the golden age of the '80s

Racing technology's return to the street was not a straight line. The BMW 2002 Turbo (1973–74) produced 170 hp and 240 lb-ft of torque, only 1,672 units could be built, with a mere 6.9:1 compression ratio, and it was never officially imported to the US. The same year, the Porsche 911 Turbo (930) offered 3.0 liters and 260 hp with its 1975 model; the performance beneath its "whale tail" spoiler came with pronounced turbo lag and a tendency for snap oversteer. These cars showed that turbo lag and drivability were still unresolved issues.

A quieter but more lasting step came from Mercedes: The OM617A turbo diesel became the first series-production turbo diesel car in the 1978 W116 sedan, opening the door to an era when turbocharging began to be associated with fuel efficiency and low emissions. In the 80s, the character diversified: The Ferrari 288 GTO (1984) produced 400 hp with its 2.8-liter twin IHI turbo V8, only 277 units were built, and it laid the foundation for the F40. The Buick Grand National / GNX (1987), with its 547-unit GNX run, brought 0-60 down to ~5 seconds and finished the quarter mile in 13.2 seconds, becoming the fastest-accelerating GM product of its time. On the Chrysler side, the 1984 Dodge Daytona and Plymouth Laser offered 146 hp Garrett turbos; the 1986 Shelby GLHS pushed this to 175 hp. The first production variable geometry turbo (VGT) application appeared in 1989 in a Chrysler CSX variant.

The Japanese manufacturers' 80s explosion

In the 1980s, Japanese manufacturers pushed the boundaries by combining turbocharging with lightweight chassis and motorsport-derived technology; the era is remembered as the "golden age" of turbocharged Nissans, rotary Mazdas, and Honda's high-revving engines. This lineage continued into the 90s with icons such as the Nissan Skyline GT-R R32–R34, Honda NSX, Mazda RX-7 FD, Toyota Supra MK4, and Subaru Impreza WRX STI. Porsche's racing side never gave up on the turbo either: The 956 of 1982 achieved one-two-three finishes at Le Mans with its 2.8-liter twin-turbo engine; The 962, developed for the US market, won 4 consecutive IMSA championships starting from 1984.

The oil crisis and downsizing: why did turbocharging come to dominate series production?

Turbocharging's second spring in street cars came not so much from performance goals as from economic necessity. After the 1973 OPEC embargo, US automobiles suffered power losses; downsizing began as a direct response to this crisis and gave rise to the CAFE fuel economy standards. Although the shift to smaller cars had begun before the first embargo, the crisis made it permanent. Before 1970, big V8s with 5.7–7.5-liter displacements and high horsepower were the standard; that picture began to close.

In modern engine downsizing, replacing large naturally aspirated engines with small turbo engines yields a 20–30% fuel economy gain; The prediction that the majority of Ford's fleet will run on EcoBoost sums up this aspect. The hot-vee layout, where the turbo is placed between the cylinder banks, also evolved from Formula 1 and was first seen in production with the BMW N63 engine; BMW and Mercedes produce over 600 hp with this layout.

What is turbo lag and how did engineering conquer it?

Turbo lag is the delay in power delivery caused by the turbine failing to reach sufficient speed the moment throttle is applied; on the 911 Turbo of the '70s, this lag was the defining feature of its driving character. The engineering answer progressed along three main lines:

• Twin-scroll turbo: It feeds exhaust gas streams to the turbine through separate channels, reducing interference and speeding up response; it requires a split inlet turbine housing and manifold.
• Parallel twin-turbo: Two smaller turbos are used; since each turbo feeds a smaller displacement, it spins faster and lag is reduced for the same power.
• Smaller turbo + efficient flow: A smaller turbine works efficiently at lower revs; the twin-scroll design optimizes this flow, significantly reducing lag.

Its historical origins should not be forgotten either: The driver-controlled boost adjustment on the Porsche 917/30 was one of the first ways lag was managed in the racing world. Today, twin-scroll and hot-vee layouts have reduced lag to a level imperceptible in everyday use.

Conclusion: from track to road, from road to engine

The history of turbocharging is the story of an approach, not a component: not losing energy. From the Saurer truck to the Jetfire, from the Offys to the RS01, from the 917/30 to the MP4/4, this lineage applied the same physical principle at different scales at every step. The post-oil-crisis downsizing wave turned this technology from an option into the standard. Today, even in hot-vee engines exceeding 600 horsepower, the same 1905 idea is at work - only far quieter, more efficient, and lag-free.

Sources

• History of the Turbocharger
• Turbo vision: a revolution in engine construction
• Turbocharger
• Downsize (automobile)
• Hot vee turbocharged engine
• Turbo Lag: Causes, Effects and Solutions
• The Lost Scrolls of Turbocharging: How Twin-Scrolls Work
• The First Turbocharged Mass-Market Production Car
• Boost Isn't New! A History of Turbocharged Cars
• History of the turbo