Summary

In 1962 and 1963, Oldsmobile offered a short-lived turbocharged version of the compact F-85. Called F-85 Jetfire, it used a high-compression aluminum V-8 engine with a complex, troublesome fluid injection system. Chevrolet also developed a simpler turbocharger installation for the air-cooled flat-six engine of the rear-engined Corvair. The Corvair offered turbocharged engines from 1962 to 1966.

In 1962, Chevrolet and Oldsmobile introduced the world’s first turbocharged production cars, the Oldsmobile F-85 Jetfire and Chevrolet Corvair Monza Spyder. In this installment of Ate Up With Motor, we’ll discuss the origins of turbocharging, the development of the Oldsmobile Jetfire, and the turbocharged Corvair that nearly stole its thunder.

IMPORTANT AUTHOR’S NOTE

This is an automotive history article, NOT a guide to repairing or modifying these cars. I AM NOT A MECHANIC. I AM NOT QUALIFIED TO PROVIDE ANY ADVICE ON TROUBLESHOOTING, REPAIRS, OR MODIFICATIONS. I CANNOT TELL YOU HOW TO TURBOCHARGE YOUR CAR. I DON’T SELL PARTS, AND I CANNOT TELL YOU WHERE TO FIND PARTS.

Oldsmobile Looks for More Power from the Rockette V-8

In the late fifties, GM’s mid-price divisions, Buick, Oldsmobile, and Pontiac, developed a new line of “senior compact” cars, which became the 1961–1963 Buick Special/Skylark, Oldsmobile F-85/Cutlass, and Pontiac Tempest/Le Mans. All three cars shared a new unitized “Y-body” shell, which had some structural commonality with the rear-engine Chevrolet Corvair, but with front-mounted engines and a longer 112-inch (2,845-mm) wheelbase. Each car offered a lightweight aluminum V-8 engine (in two distinct versions, discussed in greater detail in the sidebar below).

As we’ve previously noted, when the 1961 Buick Special, Oldsmobile F-85, and Pontiac Tempest arrived, they were clearly positioned as economy cars, offered only in four-door sedan and wagon forms. Two-door coupes, fancier trim, and (except for Pontiac) more powerful engine options arrived quite late in the model year, probably as a reaction to the popular new Monza version of the Corvair.

Therefore, it’s somewhat surprising to learn that the possibility of supercharging the Olds F-85’s aluminum “Rockette” V-8 was first broached in the fall of 1959, a full year before the 1961 F-85 went on sale and almost 18 months before the introduction of the sportier F-85 Cutlass coupe. Exactly why Oldsmobile was so interested in extracting more power from the Rockette engine at that stage is no longer entirely clear; Gilbert Burrell, Oldsmobile’s chief engine development engineer, said later that it was a response to an emerging market for sporty compacts, but at the time, the introduction of the Corvair Monza was still months away, and if Oldsmobile anticipated a demand for sportier models, there was no evidence of that in the initial merchandising of the F-85.

The more probable explanation is that Oldsmobile was concerned about the Rockette V-8’s growth potential. The 215 cu. in. (3,528 cc) aluminum V-8 was light and relatively economical, but its compact size left little room for bore and stroke increases, and because Buick supplied the engine blocks, Oldsmobile couldn’t increase the engine’s displacement without Buick’s cooperation. The high-compression Cutlass engine would have an additional 30 gross horsepower (22.4 kW), but most conventional means of increasing horsepower much beyond that level would come at the expense of low-end torque and driveability. In the short term, the Rockette was certainly adequate — even in regular-fuel form, its 155 gross horsepower (115.6 kW) made it one of the most powerful engines in its class — but if that changed, Oldsmobile wouldn’t have many practical options. The Y-body engine compartment was cramped enough that even the compact aluminum V-8 was a tight fit, so installing the division’s larger V-8 would likely have required major surgery.

As Burrell was no doubt aware, the fifties had seen a modest renaissance in mechanical supercharging: using an air compressor to force air and fuel into the cylinders of an engine at higher than atmospheric pressure. Superchargers were popular aftermarket accessories at the time, and Kaiser, Studebaker-Packard, and (briefly) Ford had all offered McCulloch centrifugal superchargers as regular production options. An engine-driven supercharger allowed big increases in power and torque using more or less bolt-on equipment that could be added to an existing engine without too much difficulty. Unfortunately, up to that point, most automotive superchargers had been expensive and rather limited in capability. They were useful in competition, to the extent racing officials were prepared to allow them, but they offered little benefit at lower engine speeds, and driving the impeller off the crankshaft via belts, gears, or chains tended to be noisy as well as consuming a significant amount of power. Their reliability had also left much to be desired, leaving them with a fairly checkered reputation in the U.S.

In considering this, Burrell recalled that the GM Research Laboratories had recently done some experimental work on turbocharging: forced induction using a centrifugal supercharger driven not by the crankshaft, but by the otherwise wasted energy of the engine’s exhaust stream.

Burrell later characterized this research as a single report that had been gathering dust for several years, but in fact a group within the Research Laboratories had recently spent about five years working on turbocharging, beginning in 1954 and continuing into early 1959. Those studies had begun with laboratory simulations and dynamometer testing of single-cylinder test engines, and progressed to include at least one Oldsmobile Rocket V-8 fitted with a turbocharger made by the Schwitzer Corporation (today part of BorgWarner) for diesel engines.

The report to which Burrell referred may have been related to a 1956 presentation by manager of Research Laboratories activities Alfred L. Boegehold, subsequently published in the trade journal Metal Progress, which examined possible directions for future automobile engines, including, among others, turbocharged aluminum Otto-cycle engines, gas turbines, and both two- and four-stroke diesels. That presentation noted that the turbocharged aluminum engine was by far the most efficient of the various engine types in terms of size and weight per horsepower, with only fractionally higher specific fuel consumption (fuel consumed per brake horsepower per hour) than a conventional cast iron engine.

Although Boegehold’s presentation dismissed the idea that turbocharged gasoline engines would be worthwhile for general passenger car use, the Research Laboratories team had continued their work, assembling an experimental turbocharged, fuel-injected 371 cu. in. (6,075 cc) Oldsmobile V-8 engine, which produced 317 hp (236.4 kW) at 4,000 rpm with 5 psi (0.34 bar) boost from a single Schwitzer turbocharger. When finally installed in a car in March 1958, the engine proved powerful enough to catapult the big Oldsmobile Super 88 to 60 mph (97 km/h) in less than 7 seconds and 100 mph (161 km/h) in less than 18 seconds, albeit with significant throttle lag at low speeds. This car was tested throughout 1958, so it seems likely that Burrell would have heard about it even if he didn’t have the opportunity to drive it himself. The Research Laboratories also conducted some experiments involving turbocharged Chevrolet truck engines, using turbochargers supplied by a California company called AiResearch, a division of the Garrett Corporation.

We should emphasize that the Research Laboratories projects had no specific production applications in mind, and the fact that some of those experiments had used Oldsmobile engines didn’t mean that the research was conducted for Oldsmobile, or even with any meaningful divisional involvement. The role of Research Laboratories work was to conduct foundational research in interesting new areas and enable the corporation to stay abreast of noteworthy recent developments, without any particular assumptions about whether or how that research might translate into production.

Blower Background

When the Research Laboratories began that work in the mid-fifties, automotive turbocharging was still largely unexplored territory, although turbocharging (sometimes called “turbo-supercharging”) was already an old idea. A patent filed by Swiss engineer Alfred Büchi (sometimes anglicized as “Buechi”) back in 1905 had proposed combining an exhaust-driven axial turbine, an axial turbo-compressor, and a radial piston engine on a common shaft. From this initial concept, Büchi subsequently developed the now-familiar freewheeling turbo arrangement, with a turbine and centrifugal compressor sharing a common shaft, but with no direct mechanical link to the engine crankshaft. Such a turbo-compressor promised a tidy solution to a problem that had been the downfall of many early attempts to supercharge internal combustion engines: the difficulty of devising a compressor and drive arrangement that would add more power than it consumed.

Although the concept of turbocharging was fundamentally sound, it presented an array of formidable design challenges. The rotating assembly had to be precisely balanced and properly lubricated to allow very high rotational speeds while also keeping the impeller and turbine sides tightly sealed and well insulated from one another — to say nothing of the problem of manufacturing a turbine capable of withstanding exhaust temperatures that in a spark ignition engine could easily exceed the melting point of aluminum.

For those reasons, the most commercially successful early applications of turbocharging were for low-speed diesel engines, whose cooler exhaust temperatures were less of a strain on contemporary metallurgy. In 1919, Büchi succeeded in arranging a deal between SLM (Schweizerische Lokomotiv und Maschinenfabrik, Swiss Locomotive and Machinery Works) and Brown, Boveri & Company to develop his turbo-supercharger designs for large diesel engines. This venture really took off following the introduction of Büchi’s improved “pulse wave” turbocharger design, patented in 1925, which further increased power through better exhaust gas scavenging. By the late thirties, Brown, Boveri & Company was making turbochargers for two- and four-stroke diesel engines with outputs ranging from 150 to 5,500 hp (112 to 4,101 kW), used in locomotives, ships, submarines, and a very wide variety of industrial applications. (The company, which is now called ABB, continued to make turbochargers through 2022, when it spun off that business as a separate company called Accelleron Industries.)

In a 1937 technical review in the Brown, Boveri & Company in-house journal, engineer Emil Klingelfuss confidently predicted that turbo-supercharging would inevitably also find widespread use in aviation, despite the significant additional problems involved in turbocharging high-speed spark ignition engines, with their much higher exhaust temperatures.

Indeed, by the late thirties, the aircraft turbo-supercharger’s hour was finally approaching after a protracted gestation. Back in 1916, Parisian engineer Auguste Rateau had patented an exhaust-driven turbo-compressor for high-speed aircraft engines, which was built and tested in 1917–1918 on a Breguet XIV A2 reconnaissance aircraft — probably the first working example of a turbocharger for spark ignition engines. Sanford Moss of General Electric (GE) had subsequently developed his own variation on the Rateau turbo-compressor, which was installed on a V-12 Liberty engine and tested on a truck-mounted dynamometer atop Pikes Peak, Colorado, in September and October 1918. However, the practical problems were far from resolved by the time of the armistice, and the lack of suitable high-temperature alloys greatly limited the lifespan of early aircraft turbochargers. Military officials remained ambivalent, preferring crankshaft-driven superchargers (although development of the latter had also been very troublesome). It was not until 1938 that U.S. Army Air Corps brass conceded that the performance benefits of turbocharging, particularly in altitude performance, were worth the bother.

World War 2 saw dramatic improvements in turbocharger technology, thanks in part to the availability of high-cobalt alloys better able to withstand the intense heat of a spark ignition engine’s exhaust gases. The use of turbo-supercharging — often in two-stage installations with separate exhaust-driven and crankshaft-driven compressors — allowed dramatic improvements in takeoff power, speed, and altitude. However, the metallurgical advances that made turbocharged military aircraft engines practical also hastened their end by accelerating the development of gas turbine engines. By war’s end, it was clear that jets would shortly relegate the most powerful aircraft piston engines to second-line duty, if not the scrapyard. At the same time, wartime turbo-superchargers were overkill for civil aviation (turbocharging wouldn’t become popular for light aircraft until the sixties) and were much too big and heavy to be repurposed for auto racing or hot rods.

After the war, turbochargers became increasingly common on smaller diesel engines, like those found in tractors and construction equipment. By the middle of the decade, there was also a growing number of turbocharged diesel engines for large trucks, offered by MAN (Maschinenfabrik Augsburg-Nürnberg, Machine Factory Augsburg-Nuremberg), Volvo, and Cummins.

Cummins had previewed its turbodiesel engine in dramatic fashion by entering a turbodiesel race car, the No. 28 Cummins Diesel Special, in the 1952 Indianapolis 500. The car was powered by an aluminum and magnesium version of the company’s 401 cu. in. (6,570 cc) diesel six, fitted with a Schwitzer-Cummins turbocharger producing up to 20 psi (1.38 bar) boost at 4,300 rpm. Driven by Freddie Agabashian, No. 28 qualified on the pole and set a one-lap speed record of 139.104 mph (223.866 km/h), but turbocharger damage from track debris took the turbodiesel car out of the running on its 71st lap, and rules changes meant that it never raced again.

Turbodiesel light trucks and passenger cars wouldn’t arrive until the seventies, so other than the Cummins Diesel Special, the only notable attempt at automotive turbocharging during this period was an aftermarket kit designed in the late thirties by Ray Besasie of Besasie Engineering in Milwaukee, Wisconsin. First advertised around 1940 and marketed again after World War 2, it produced about 3 psi (0.21 bar) boost at 22,000 to 30,000 rpm, which Besasie claimed was good for a 25 percent increase in engine power. Few were sold, and we’re not sure how durable they were; the Besasie turbocharger was essentially a shade-tree engineering project. Nonetheless, some of Ray Besasie’s family and friends claim that GM engineers consulted with Besasie as part of the corporation’s early turbocharger research.