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December 22, 2005
Motoring Memories:
Chevrolet Corvair Spyder Turbocharged
Story and photo by Bill Vance
The
compact Corvair, which Chevrolet introduced in 1960, had an aluminum,
horizontally-opposed (flat), air-cooled six-cylinder engine located in
the rear, and four wheel independent suspension. This put it away out of
the mainstream of an American auto industry dominated by big cars with
front-mounted cast iron V8s driving through a solid rear axle.
The
Corvair was inspired by the top-selling German Volkswagen, and along
with cars like the Ford Falcon, Chrysler (later Plymouth) Valiant and
American Motors Rambler, was meant as an import fighter.
But
if the Corvair wasn't different enough already, Chevrolet took it even
further off the beaten path in 1962 when, along with Oldsmobile, it
pioneered turbocharging in production automobiles.
A
turbocharger, short for turbine-driven supercharger, is an ingenious
engineering device that produces what could almost be called "free"
horsepower. By inserting a small turbine in the exhaust stream, and
using it to spin an air compressor to pump more air into the engine,
significant horsepower increases can be achieved.
The
turbocharger was invented by Alfred Buchi, a Swiss engineer, in 1905.
Supercharging appealed to aeronautical engineers trying to maintain low
altitude performance at high altitudes. The turbocharger was a natural
solution to this problem, and during the First World War French engineer
Auguste Rateau developed a turbocharged aircraft engine.
But
if Alfred Buchi invented the turbocharger, it was Dr. Sanford Moss of
General Electric in the United States who matured it. He could be called
the "Father of Turbocharging." In 1918 Dr. Moss fitted a turbocharger
to a First World War Liberty V-12 aircraft engine and tested it on top
of Pikes Peak using a truck-mounted dynamometer. At that elevation,
4,267 m (14,000 ft) above sea level, the Liberty's horsepower increased
from 221 without the turbo, to 356 with it, a dramatic demonstration of
turbocharging's effectiveness.
Turbo development continued during the 1920s and '30s, and was given
another push during the Second World War when virtually all military
aircraft would have them. They were also used on large industrial
engines, usually diesel, and found their way onto transport trucks,
particularly in mountainous regions.
Some
hot rodders and racers were experimenting with turbos during the 1950s,
but it wasn't until the '60s that they would be fitted to production
cars.
In
the spring of 1962 both Chevrolet and Oldsmobile introduced turbocharged
models. Oldsmobile put a turbo on its 3.5 litre (215 cu in.) aluminum V8
F-85 intermediate model and called it the "Jetfire." The turbo increased
horsepower from the best non-turbo figure of 185, to 215, or one
horsepower per cubic inch.
Chevrolet applied turbocharging to its Corvair to increase its power and
enhance its sporting image. The Ford Falcon and the Valiant, the
Corvair's direct competitors, had conventional front engine designs so
they could easily be fitted with larger engines. This was not so easy in
the Corvair.
Although the Corvair's air-cooled six could be increased in displacement
from its original 2.3 litres (140 cu in.), there were definite limits on
how big it could go. It went to 2.4 litres (145 cu in.) in 1961, and 2.7
(164) in 1964, but that's as far as it went during the Corvair's 10-year
life span. Chevrolet engineers therefore chose turbocharging as their
route to substantially more power.
In
1962 the Corvair's normally aspirated base engine developed 80
horsepower, or 84 when fitted with the optional "Powerglide" automatic
transmission. When the turbocharged Corvair Spyder was introduced it had
150 horsepower, almost double the power out of the same displacement!
This improved performance significantly.
Car
Life magazine (8/62) tested a pair of Corvairs. One was a "town or
touring" automatic-equipped Monza coupe with the 84 horsepower engine.
They recorded a more than modest zero to 96 km/h (60 mph) time of 21.6
seconds, and a top speed of 145 km/h (90 mph).
The
"fun and games" Spyder coupe was a whole different matter. Fitted with a
four-speed manual transmission, the 150 horsepower turbocharged Corvair
would sprint to 96 (60) in 10.8 seconds, and reach a top speed of 169
km/h (105 mph). The testers said the turbo "puts this compact into a
class by itself."
While Oldsmobile would stay with turbocharging for only a couple of
years - 1962-'63 - before succumbing to bigger engines as an easier,
less complex route to higher power, Chevrolet would keep its turbo until
1966. Horsepower of the Corvair turbo was increased to 180 in 1965.
Unfortunately for the Corvair, 1965 was the year in which Ralph Nader
published his book Unsafe At Any Speed. In Unsafe he savaged the Corvair
for alleged unsafe handling due to the swing rear axles fitted to the
1960-64 models. Ironically, by the time the book appeared, Chevrolet had
replaced the swing axles with a fully articulated rear suspension. The
damage was done, however, and the Corvair went into a steep sales
decline; it was discontinued in 1969.
While the Corvair came to a sad end, it and Oldsmobile did pioneer
production automobile turbocharging, and demonstrate its potential. It
would be another decade before it would return, this time from Porsche
in the 1975 911 Turbo Carrera.
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