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Wikipedia: Chevrolet Corvair
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History
The following section is an excerpt from Wikipedia's Chevrolet Corvair page on 5 June 2017, text available via the Creative Commons Attribution-ShareAlike 3.0 Unported License.
The Chevrolet Corvair is a compact automobile manufactured and marketed by Chevrolet for model years 1960–1969 over two generations.
As the only American-designed, mass-produced passenger car to use a rear-mounted air-cooled engine, the Corvair model range included a two-door coupe, convertible, four-door sedan, and four-door station wagon body styles, as well as passenger van, commercial van, and pickup truck variants.
The Corvair competed with imported cars such as the original Volkswagen Beetle as well as the Ford Falcon, Plymouth Valiant, Studebaker Lark and the Rambler American.
The Corvair's legacy was affected by controversy surrounding its handling, scrutinized in Ralph Nader's Unsafe at Any Speed, along with the then GM's top management resorting to unethical measures to handle the issue, as well as a 1972 Texas A&M University safety commission report for the National Highway Traffic Safety Administration which found that the 1960–1963 Corvair possessed no greater potential for loss of control in extreme situations than its contemporaries.
The name "Corvair" is a portmanteau of Corvette and Bel Air. The name was first applied in 1954 to a Corvette-based concept with a hardtop fastback-styled roof.
In 1952, Ed Cole was promoted to chief engineer of the Chevrolet Motor Division. Four years later, in July 1956, he was named general manager of Chevrolet — GM's largest automotive division — and a vice president of General Motors. At Chevrolet, Cole pushed for many of the major engineering and design advancements introduced in the Chevrolet car and truck lines between 1955 and 1962. He was the moving force behind the development and production of the rear-engined, air-cooled Corvair. Despite its infamous history, the Corvair was a ground-breaking car in its day. As chief engineer, he was heavily involved in the development of the Corvette sports car. He is also known as the "father" of the small block Chevy V8, one of the most celebrated engines in American automotive history.
Until 1960, the "Big Three" American domestic auto manufacturers (General Motors, Ford, and Chrysler) produced only one basic size of passenger car: large. However, a successful modern "compact car" market segment was established in the U.S. by the 1950 Nash Rambler. Moreover, imports from Europe, such as Volkswagen, Renault, and Fiat, showed that there was demand in the U.S. for small cars, often as a second car or an alternative for budget-minded consumers. While the "Big Three" continued to introduce ever-larger cars during the 1950s, the newly formed American Motors Corporation (AMC) focused its business strategy on smaller-sized and fuel-efficient automobiles, years before there was a real need for them. Because it was a small company compared to the Big Three U.S. automakers, AMC positioned itself as a "dinosaur-fighter" and its compact-sized Rambler models rose to third place among domestic automobile sales. American Motors also reincarnated its predecessor company's smallest Nash model as the "new" 1958 Rambler American for a second model run, an almost unheard of phenomenon in automobile history.
During 1959 and 1960, the Big Three automakers planned to introduce their own "compact" cars. Ford and Chrysler's designs were scaled-down versions of the conventional American car, using four- or six-cylinder engines instead of V8s, and with bodies about 20% smaller than their standard cars.
An exception to this strategy was the Chevrolet Corvair. Led by General Manager Cole, Chevrolet designed a new car deviating from the traditional American norms of design. The car was powered by an air-cooled horizontally opposed six-cylinder engine constructed with many major components made from aluminum. The engine was mounted in the rear of the car, driving the rear wheels through a compact transaxle. Suspension was independent at all four wheels. There was no conventional chassis, being the first unibody built by Fisher Body. The tires were an entirely new wide low-profile design. The styling was unconventional for Detroit: subtle and elegant, with no tailfins or chrome grille. Its engineering earned numerous patents, while Time magazine put Ed Cole and the Corvair on the cover, and Motor Trend named the Corvair as the 1960 "Car of the Year".
First generation (1960–1964)
The 1960 Corvair 569 and 769 series four-door sedans were conceived as thrift cars offering few amenities in order to keep the price competitive, with the 500 (standard model) selling for under $2,000. Powered by the Turbo Air 6 engine 80 hp (60 kW; 81 PS) and three-speed manual or optional extra cost two-speed Powerglide automatic transmission, the Corvair was designed to have comparable acceleration to the six-cylinder full-size Chevrolet Biscayne. The Corvair's unique design included the "Quadri-Flex" independent suspension and "Unipack Power Team" of engine, transmission and rear axle combined into a single unit. Similar to designs of European cars such as Porsche, Volkswagen, Mercedes-Benz and others, "Quadri-Flex" used coil springs at all four wheels with independent rear suspension arms incorporated at the rear. Specially designed 6.5 in by 13 in. 4-ply tires mounted on 13 inch wheels with 5.5 in. width were standard equipment. Available options included RPO 360, the Powerglide two-speed automatic transmission ($146), RPO 118, a Gasoline Heater ($74), RPO 119, an AM tube radio ($54), and by February 1960 the rear folding seat (formerly $32) was standard. Chevrolet produced 47,683 of the 569 model and 139,208 769 model deluxe sedans in 1960. In January 1960, two two-door coupe models were introduced designated as the 527 and 727 models. Following the success of the upmarket "Mr. and Mrs. Monza" styling concept cars at the 1960 Chicago Auto Show, management approved the neatly appointed bucket-seat DeLuxe trim of the 900 series Monza as a two door club coupe only. This model began arriving at showroom floors in April 1960. Despite their late January introduction of the coupe, these cars sold very well; about 14,628 base model 527 coupes, 36,562 727 deluxe coupes and 11,926 927 Monza club coupes, making the coupe one of the most popular Corvairs.
Sales figures revealed to Chevrolet management that the Corvair was more of a specialty car than a competitor to the conventionally designed Ford Falcon or Chrysler's Valiant. Corvair was not as competitive in the economy segment and Chevrolet began a design program that resulted in a compact car with a conventional layout, the Chevy II, for the 1962 model year.
An available option on the Corvair introduced in February 1960 was RPO 649, a more powerful engine, the "Super Turbo Air". Super Turbo Air was rated at 95 hp (71 kW; 96 PS) at 4,800 rpm and 125 ft.lbs. at 2,800 rpm due to a revised camshaft, revised cylinder heads with dual springs, and a lower restriction muffler with a 2" outlet. This option was available in any Corvair model. However, in 1960, RPO 649 was not available with RPO 360, the Powerglide automatic transmission.
The Corvair was Motor Trend magazine's Car of the Year for 1960. A station wagon body-style, marketed as the Lakewood joined the lineup in 1961.
Second generation (1965–1969)
The Corvair second generation arrived for model year 1965, noted for its lack of a "B" pillar and a new fully independent suspension replacing the original swing axle rear suspension. The Corvair used coil springs at each wheel.
New refinements appeared on the 1965 redesign. The Corsa came standard with an instrument panel featuring a 140 mph (230 km/h) speedometer with resettable trip odometer, a 6,000 rpm tachometer, cylinder head temperature gauge, analog clock with a sweeping second hand, a manifold vacuum/pressure gauge and fuel gauge. A much better heater system, larger brakes borrowed from the Chevelle, a stronger differential ring gear, a Delcotron alternator (replacing the generator), and significant chassis refinements were made. AM/FM stereo radio, in-dash All Weather Air Conditioning, telescopically adjustable steering column, and a Special Purpose Chassis Equipment ("Z17") handling package, consisting of a special performance suspension and quick ratio steering box, were significant new options for 1965. The Monza and Corvair 500 Sport Sedans were the only compact cars ever available in the U.S. as pillarless four door hardtops.
By this time, the station wagon, panel van, and pickup body styles had all been dropped and 1965 was the last year for the Greenbrier window van, which was retained mainly for fleet orders, with 1,528 being built. In all, 235,528 Corvairs were built in 1965. Chevrolet replaced the Corvair-based vans with the Chevrolet Sportvan/GMC Handi-Van, which used a traditional front engine/rear drive axle borrowed from the Chevy II.
Handling issues
The first-generation Corvair featured a rear engine + swing axle design similar to that of the Renault Dauphine and Volkswagen Beetle – a design which eliminates universal joints at the wheels and keeps the rear wheels perpendicular to the half-shafts. The design can allow rear tires to undergo large camber angle changes during fast cornering due to side g-forces causing "rebound" camber and decreasing the tread contact with the road surface, leading to a loss of rear wheel grip and oversteer—a dynamically unstable condition where a driver can lose control and spin. The problem is most severe with rear-engine swing axle combinations because of the greater inertial mass over the rear wheels and the higher center of gravity during rebound camber conditions. The additional high weight of a station wagon body also exacerbates the tendency. Oversteer is exacerbated by deceleration during cornering due to increased side g-force and lightened load on rear tires (lift-off oversteer). Understeer is common in front-engine cars, due to more weight, and inertia, on the front tires. Both conditions are dangerous when a car is driven at its cornering limits.
Consumer protection activist Ralph Nader addressed the handling issues of the first-generation (1960–1963) Corvair in his 1965 book: Unsafe at Any Speed. GM had over 100 lawsuits pending in connection with crashes involving the Corvair, which subsequently became the initial material for Nader's investigations. The book highlighted crashes related to the Corvair's suspension and identified the Chevrolet suspension engineer who had fought management's decision to remove—for cost reasons—the front anti-sway bar installed on later models. Nader said during subsequent Congressional hearings, the Corvair is "the leading candidate for the un-safest-car title". Subsequently, Corvair sales fell from 220,000 in 1965 to 109,880 in 1966. By 1968 production fell to 14,800. Public response to the book played a role in the National Traffic and Motor Vehicle Safety Act in 1966.
A 1972 safety commission report conducted by Texas A&M University concluded that the 1960–1963 Corvair possessed no greater potential for loss of control than its contemporary competitors in extreme situations. The U.S. Department of Transportation (DOT) issued a press release in 1972 describing the findings of NHTSA testing from the previous year. NHTSA had conducted a series of comparative tests in 1971 studying the handling of the 1963 Corvair and four contemporary cars—a Ford Falcon, Plymouth Valiant, Volkswagen Beetle, and Renault Dauphine—along with a second-generation Corvair (with its completely redesigned, independent rear suspension). The 143-page report reviewed NHTSA's extreme-condition handling tests, national crash-involvement data for the cars in the test as well as General Motors' internal documentation regarding the Corvair's handling. NHTSA went on to contract an independent advisory panel of engineers to review the tests. This review panel concluded that "the 1960–63 Corvair compares favorably with contemporary vehicles used in the tests [...] the handling and stability performance of the 1960–63 Corvair does not result in an abnormal potential for loss of control or rollover, and it is at least as good as the performance of some contemporary vehicles both foreign and domestic." Former GM executive John DeLorean asserted in his book On a Clear Day You Can See General Motors that Nader's criticisms were valid.
Journalist David E. Davis, in a 2009 article in Automobile Magazine, noted that despite Nader's claim that swing-axle rear suspension were dangerous, Porsche, Mercedes-Benz, Tatra, and Volkswagen all used similar swing-axle concepts during that era. (The handling of other rear-engine swing-axle cars, particularly the Volkswagen Type I and II, has been criticized as well.) Some contend that Nader's lack of an automotive engineering degree or a driver's license at the time he wrote Unsafe at Any Speed disqualifies him as a critic of automotive safety. In response to Nader's book, Mechanix Illustrated reviewer Tom McCahill tried to get a 1963 Corvair to flip, at one point sliding sideways into a street curb, but could not turn over the vehicle.
| Date | Media or Collection Name & Details | Files |
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| 1960 | The Corvair in Action! Chevrolet |  Topic Page - 6:28 |
| Date | Document Name & Details | Documents |
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| 28 March 1967 | NHTSA Recall 67V033000 1967 Chevrolet Corvair Steering:Wheel And Handle Bar National Highway Traffic Safety Administration | Recall Page - 1 page |
