There is no American automobile more controversial than this one. It’s the car that launched the career of Ralph Nader and led directly to the passage of the first U.S. federal safety legislation. Automotive historian Michael Lamm called this car a martyr; others said it should never have been built at all. It was flawed, at least in its original iteration, but it was also one of the most daring cars GM has ever built. We’re talking about the Chevrolet Corvair.
Author’s Note: The original version of this article was written in 2007. It has been extensively revised and expanded, adding new information and correcting various factual errors. WARNING: The article contains animated GIF images.
THE WRECK OF THE CADET
Once upon a time, Chevrolet, Ford, and Plymouth were known collectively as “The Low-Priced Three.” That did not, however, mean that their cars were particularly small by the standards of the rest of the world. In 1934, for example, a Chevrolet Master Six was 175 inches (4,445 mm) long on a 112-inch (2,845mm) wheelbase; the dimensions of the contemporary Ford and Plymouth were very similar. The Chevrolet weighed perhaps 3,200 lb (1,450 kg) at the curb and was powered by a 207 cu. in. (3,389 cc) six, which would have made it a very expensive proposition in England, France, or Italy, with those countries’ displacement-based taxable horsepower rules. Furthermore, the car and its engine would grow progressively bigger. Thanks to the pressures of the annual model change and the constant one-upmanship of its key rivals, the 1942 Chevrolets — the last available before America entered World War II — were more than a foot and a half (527 mm) longer than their 1934 ancestors. With the greater size came greater weight, more power, and a steady erosion of fuel economy.
Deploring that trend, some Chevrolet engineers had pushed for a smaller compact model as early as the mid-1930s, albeit with very little success. The primary obstacle was profit. Small cars cost almost as much to build as large ones, but larger models could be sold for higher prices. As a result, the division’s management and salesmen had little enthusiasm for compact cars. During the war, however, Chevrolet general manager Marvin E. Coyne became concerned about the prospects of a postwar recession like the one that had followed the Great War. As a potential stopgap, he asked engineer Earle S. MacPherson, then the head of Chevrolet’s Experimental engineering unit, to devise an inexpensive compact car to supplement the division’s full-size models.
In early 1945, MacPherson’s group started work on a compact “Light Car,” subsequently christened “Cadet.” The Cadet was a smallish four-door sedan, riding a 108-inch (2,743mm) wheelbase. Its target weight was about 2,200 lb (1,000 kg) and the intended engine was a 133 cu. in. (2,173 cc) OHV six making about 65 hp (48 kW). The Cadet was modestly sized, frugal, and reasonably nimble, using an early version of what is now known as MacPherson strut suspension both front and rear. Its target price was just under $1,000, or about 10% cheaper than the least-expensive full-size Chevy.
GM announced its intention to build the Cadet in May 1945, but the car’s internal support was limited. Corporate chairman Alfred P. Sloan opposed it, as did Chevrolet chief engineer James Crawford and much of the Chevrolet sales organization. To make matters worse, the Cadet was running well over its cost targets, frustrating Coyne’s hopes of a sub-$1,000 price tag. When Coyne departed to become vice president of the car and truck group in June 1946, the project began to lose momentum. In September, GM announced that production plans for the Cadet had been suspended. In May 1947, the Light Car was transferred from Chevrolet to the central Engineering staff to continue as a pure research project. MacPherson resigned that September and went to Ford.
Compact projects at Ford and Chrysler met a similar fate for many of the same reasons. Ford’s own Light Car was eventually sold to Ford SAF to become the 1949 French Ford Vedette while Chrysler’s four-cylinder A-106 was simply canceled. Some of MacPherson’s ideas for the Cadet found their way into the English Ford Consul and Zephyr in 1950, but Ford’s first postwar U.S. designs were standard-size cars.
As the 1950s dawned, only America’s smaller independent automakers still seemed interested in compacts. As we have previously seen, Nash unveiled its compact Rambler in April 1950, followed that fall by Kaiser-Frazer‘s Henry J. Initial sales were promising and the Rambler and Henry J were soon joined by the Aero Willys and the Hudson Jet. Unfortunately, the U.S. market was not yet prepared to absorb more than about 150,000 compacts a year, a volume insufficient to sustain so many competitors. By the 1956 model year, the Rambler and the tiny Nash Metropolitan were the only survivors and even their volume was trivial by Ford or Chevrolet standards.
The swift collapse of the domestic compacts validated the prejudices of Big Three executives, most of whom disdained the very idea of smaller cars. It would take both passion and desperation to convince the big Detroit automakers to enter that market.
THE PASSIONS OF ED COLE
Edward Nicholas Cole was born in the tiny Michigan farming village of Marne on September 17, 1909. From an early age, he displayed a fascination with machinery and by the time he was 16, he owned two cars — wrecks that he bought and rebuilt himself with money he earned milking cows and building and selling radio kits. Although he studied pre-law at Grand Rapids Junior College, Cole enrolled in the General Motors Institute (GMI, now Kettering University) in 1930, spending half his time in class, the other half working for Cadillac. He secured a permanent position at Cadillac in 1933.
In 1941, Cole adapted Cadillac’s L-head V8 engine for use in the Army’s M-5 Stuart light tank, a project that earned him a promotion to chief industrial design engineer in 1943. He became chief engineer of Cadillac in 1946 and subsequently led the development of Cadillac’s pioneering OHV V8, which along with the contemporary Oldsmobile Rocket V8 set the standard for almost all American engines of the fifties and sixties.
Shortly after the start of the Korean War, Cole was reassigned to run Cadillac’s Cleveland Tank Plant, a demanding and politically sensitive position. In June 1952, Chevrolet general manager Tom Keating brought him back to Detroit to become Chevrolet’s chief engineer, one of GM’s most important engineering jobs. Charged with breathing new life into Chevrolet’s conservative product line, Cole shepherded the development of the first Corvette, the small-block V8, and the much-beloved ’55 Chevy. Cole dramatically increased the size and power of Chevrolet’s engineering staff, expanding it from 851 to almost 2,900 employees. He also brought in several of his old colleagues from Cadillac, including Kai Hansen and Harry Barr, who had managed the development of the Cadillac OHV V8.
Emboldened by the tremendous success of the 1955 Chevrolet, Cole began pondering the idea of a smaller companion model for Chevrolet along the lines of the old Cadet. The business case for such a car was still not strong, but despite the failure of the Kaiser, Willys, and Hudson compacts, the small car market was showing signs of life. Volkswagen, which had sold fewer than 300 cars in America in 1950, was beginning a period of spectacular growth. Its sales increased by a factor of ten from 1954 to 1955 and expanded almost five-fold for 1956. Moreover, sales of AMC’s Rambler, which now had the domestic compact market almost to itself, were beginning to rebound.
Beyond the marketing considerations, Cole was fascinated with the engineering possibilities of an all-new small car. Even while they were building tanks in Cleveland, Cole, Barr, and Hansen had spent their spare time brainstorming ideas for radical new cars. At the time, such talk had been only an intellectual exercise, but they now had the opportunity to explore those ideas more fully.
In the mid-fifties, each GM division still handled much of its own research and development work. In 1955, Cole ordered Chevrolet R&D director Maurice Olley to compare the merits of various layouts and powertrain configurations, including front-engine/rear-drive (FR), front-engine/front-wheel-drive (FF), and rear-engine/rear-drive (RR). The FR configuration was abandoned early on, mainly for packaging reasons — a conventional prop shaft and rear axle would have taken up too much space. Front-wheel drive was quickly discarded as well, in part because the very heavy, often balky steering of most contemporary FF cars was deemed unacceptable.
The rear-engine, rear-drive (RR) layout, then used by Volkswagen, Renault, and Fiat, among others, offered packaging, weight, and traction advantages as well as the prospect of lighter steering. This was in keeping with Cole’s own thoughts on the matter; he had been interested in rear engines since at least 1941 and had even developed an experimental rear-engine Cadillac shortly after the war.
With that decision, other parameters for the new car began to take shape. For example, the rear-engine layout dictated the use of independent rear suspension while weight and space considerations called for monocoque construction, a real departure for Chevrolet. Although GM’s European Vauxhall and Opel subsidiaries had adopted unitary construction in 1937, all of the corporation’s North American cars were body-on-frame. The upshot was that the new car would be truly all new — the closest Chevrolet had come to a clean sheet of paper since the ill-fated Cadet.
DOWN UNDER AND TO THE REAR
In July 1956, Ed Cole took Tom Keating’s place as vice president and general manager of Chevrolet, promoting Harry Barr to chief engineer. Cole could have taken that opportunity to propose the rear-engine compact idea to senior management, but he probably recognized that at that point, the corporation was unlikely to approve any compact car proposal, much less one as radical as Cole had in mind.
To keep senior management from learning of the rear-engine car before he was ready to make a formal presentation, Cole disguised it as a development program for Holden, GM’s Australian subsidiary, even assigning Holden part numbers to the new components and using Holden stationery and purchase order forms. (In the fifties, Chevrolet regularly did R&D work for both Holden and Opel, so this was a reasonably plausible cover story.) Even the styling development was assigned to Ned Nickles’ Experimental group rather than the Chevrolet studio.
Perhaps the most challenging aspect of the new car’s design was the engine. Cole, Olley, and project engineers Al Kolbe and Robert Benzinger decided that water cooling was impractical with the RR layout, so the car would need an all-new air-cooled engine. Kolbe and Benzinger quickly concluded that the engine needed to be a six; a four would have been simpler, cheaper, and more economical, but wouldn’t be smooth enough for American tastes. For packaging reasons, the project engineers also eschewed inline sixes in favor of a horizontally opposed “boxer” engine, which would offer good balance without the need for counterweights.
This was not Chevrolet’s first venture into air cooling. Back in the early 1920s, research boss Charles Kettering had developed a unique “Copper-Cooled” four, which was launched — despite the objections of Alfred Sloan, then on GM’s advisory committee — in early 1923. The engine was both difficult to assemble and disastrously unreliable, so fewer than 800 cars were built before the plug was pulled. Only about 100 of those cars were actually sold, all of them soon recalled. According to (unlikely) legend, many were dumped into Lake Erie, although a small handful have survived; one is at The Henry Ford in Dearborn, Michigan; another is at the National Automobile Museum in Reno, Nevada; the engine of a third car is part of GM’s Heritage Collection; and the body of a fourth car is displayed in the Buick Gallery and Research Center at the Sloan Museum in Flint.
With an air-cooled flat six, however, Chevrolet was in largely uncharted territory. Although Porsche would later build successful air-cooled sixes for more than 30 years, the first six-cylinder 911 was still seven years in the future when the Chevrolet project began. Air-cooled twins and fours were common enough in motorcycles and small European cars and Tatra had a 2,472 cc (151 cu. in.) air-cooled V8, but at that time, air-cooled flat sixes were mostly found in aircraft, tanks, or industrial applications, all of which had manufacturing requirements and operating characteristics too different from those of mass market passenger car engines to offer much in the way of useful precedent.
An additional challenge was weight. To keep weight distribution to manageable proportions, the engine’s target weight was only 288 lb (131 kg). To achieve that, Cole proposed making the engine all-aluminum and casting it in symmetrical top and bottom halves, joined at the horizontal centerline. To obviate the need for separate cylinder liners, he also wanted to use a special high-silicon aluminum alloy (akin to the A390 alloy later used in the engine of the Chevrolet Vega). Both of these ideas proved to be well beyond Chevrolet’s practical manufacturing capabilities, so the final engine design ended up with detachable cast-iron cylinder barrels, a two-piece aluminum crankcase, and detachable aluminum cylinder heads with integral intake manifolds. In final form, the engine weighed 294 lb (133 kg) with automatic transmission flex plate and torque converter housing, 332 lb (151 kg) with clutch and flywheel — light compared to most contemporary inline sixes, but still over its original design target.
Valve actuation was via pushrods and rocker arms (pivoted on rocker studs like those of Chevrolet’s contemporary small block V8) driven by a single gear-driven camshaft, carried in the crankcase below the crank. Unlike most European engines of the time, the engine used hydraulic lifters, which were an engineering headache, but eliminated the need for routine valve adjustments. Valve diameters were small and valve timing was deliberately mild, trading breathing capability and ultimate power for low-end torque. The same was true of the standard carburetion setup, which used one single-venturi Rochester carburetor for each cylinder bank.
Engine cooling was provided by an 11-inch (279mm) 24-blade engine-driven fan. For packaging reasons, the fan was mounted horizontally, driven by a torturous-looking “mule drive” belt that also operated the generator. There was also a thermostatically controlled oil-to-air oil cooler, mounted adjacent to the oil pump.
The engine’s position precluded the use of the live axle rear suspension common to all fifties Chevrolets (including the Corvette), so the rear-engine car had swing-arm rear suspension, using the axle halfshafts as control arms. Robert Schilling, who in early 1956 replaced Maurice Olley as director of research, attempted to counteract some of the oversteer inherent to swing-axle designs by supplementing the halfshafts with semi-trailing arms, but as we’ll see, this was not entirely successful.
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Yeah, to all intents and purposes the prototype Chev Cadet became our beloved Holden 48/215 or sometimes referred to as the “FX”.
Well, sort of. The 195-Y-15 prototype that became the basis of the Holden FX was a predecessor of the Cadet, built well before the war. It had a few general similarities to the Cadet (including unibody construction and a smaller version of the Stovebolt Six), but it was quite different in packaging and dimensions. (Notably, it did not have strut suspension.) It’s probably fairer to say the Cadet would have been a cousin of the Holden FX; they have a common ancestor, but they followed different paths. Also, the Holden was well along in its development when the Cadet was canceled, so it wasn’t shipped off, the way Ford sent its Light Car to become the French Ford Vedette.
So both the 195-Y-15 / Holden FX and GM Cadet basically used a smaller version of the (2nd gen?) Chevrolet Straight-6 that formed the basis of the Holden Straight-6 engine?
Guess it would partly explain why the Holden Straight-6 was never able to grow beyond a displacement of 3.3-litres to a size closer to 4-litres.
The engine intended for the Chevrolet Cadet was NOT the Holden Grey Motor used in the Holden 48/215. Where the Grey Motor was largely a scaled-down Chevrolet six, the Cadet engine had a variety of experimental features, including front and rear flywheels, and different bore/stroke dimensions. The similarity in displacement is coincidental; the Cadet engine was oversquare, with a short 3-inch (76.2mm) stroke, where the Holden was undersquare, with a 3 1/8th-inch (79.4mm) stroke. I don’t think they had the same bore spacing, although the Cadet’s was altered during development at least once.
I don’t have sufficiently detailed specs for the Cadet engine to judge how much of its basic architecture was miniaturized Stovebolt; my guess is “some” (the gear-driven cam, for instance), though not all.
The limiting factor on the Holden engine’s displacement was probably the bore spacing, which as best I can find was 3.75 inches (95.3mm) for the Grey and 4.05 (102.7mm) for the Red.
Interested to know whether the Bedford / Vauxhall Straight-6 shares any relation to the Chevrolet Straight-6, though have heard it is significantly different to the Holden Straight-6 engine.
Could a production Chevrolet Cadet have helped GM in other respects regardless of whether it is actually a success or not? Potentially even butterflying away the Corvair in favor of a more conventional layout?
I’m not terribly familiar with the Velox six. I believe it does share the same bore spacing as the Holden Grey Motor, although not necessarily a whole lot else.
The Cadet would probably not have done Chevrolet any particular commercial favors at the time. I don’t think the Chevrolet sales organization knew (or was interested in figuring out) how to sell it to postwar American buyers whose interest in smaller cars was, at that point, driven more by sticker shock more than anything else. From a technological standpoint, I don’t know that it was substantially more conventional or less eccentric than the later Corvair except in having a FR layout. Some of its advanced features seem not so much prescient as just odd — for instance, the dual flywheels were intended to reduce driveline intrusion by allowing the rear flywheel to be smaller in diameter, which seems an expensive approach to a fairly incremental gain. MacPherson’s original strut suspension layout wasn’t as tidy or cost-effective as the later version (developed after he left for Ford and of course now very common.)
The configuration of the Corvair seems to have been dictated in large part by the fact that Ed Cole thought it would be neat and had been toying with similar ideas since around the time the Cadet was developed. There was a rationale to some of it (the desire to have low-effort manual steering, for instance), but not necessarily a compelling one compared to the advantages of a conventional smaller car, as quickly evidenced not only by the Falcon, but also by Chevrolet’s own Chevy II.
So, whether the Cadet would have had an influence would have really depended a lot on how long it was around and how well it had done. If Chevrolet had done well enough with it to justify keeping it around until 1957, when the Corvair was developed, it would have made the rationale for building the Corvair and the latter would have probably remained an engineering exercise. If the Cadet had eked out a few years before being canceled (or foisted on Holden, Opel, or Vauxhall), it may not have made any difference, especially if the tooling were gone by then.
One possible effect might have been to get Chevrolet to continue developing strut-type suspension, although how that might have played out is hard to judge and would depend a lot on how broadly it was adopted. A first-generation Corvair with all-strut suspension might have been spared most of the actual car’s handling oddities, so there’s that.
I’m a big Corvair fan, and own 5 Corvairs. 3 Early ‘verts, including a Spyder, and a ’66 Fitch Sprint and a ’62 Rampside.
I read your piece top to bottom, and enjoyed being reminded of the facts. Thank you, Corvairwild
I just want to thank you for your fantastic effort in documenting the inner workings of the car industry, always informative and always entertaining! In each article I learn things I even did not know that I wanted to learn… :)
It is great to learn the “American” (as in U.S.A.) automotive history since I have only an European perspective – and I can not wait until You take a look at similar cases concerning the Japanese and Korean car manufacturers! ;-D
We have done a couple of Japanese cars — the Datsun 510 and 240/260/280-Z, the Lexus LS400, and the Lexus SC/Toyota Soarer — and there will be more in the future. (I’d love to tackle the Mazda RX-7 and Subaru SVX at some point, the Honda Civic CRX is likely, and there will most definitely be an NSX article.) The Korean automakers are probably not going to be popping up any time soon, but I certainly wouldn’t rule it out.
The 55 nomad had a 265CID not a 262
Whoops, that’s a typo. Fixed.
In the article, you mention that early Corvairs had rear swing axle suspension. I think early VWs and Triumph Spitfire had a similar arrangement. Did any (other) cars of the late 1940s or 1950s have a more sophisticated independent rear suspension arrangement (Jaguar, Tucker or others)? Thanks
That’s a good question. Some race cars adopted true double-wishbone suspensions, but I don’t know of any forties or fifties production cars that used that set-up, mainly for cost reasons. Jaguar’s independent rear suspension was developed contemporaneously with the Corvair, but it didn’t appear in production until the debut of the E-Type in 1961.
The three major alternatives to swing axles in the late fifties and early sixties were the de Dion axle, “low-pivot” swing axles, and trailing arms. The de Dion, which was popular for racing, but used only sporadically on production cars, was not really an independent suspension; it mounted the differential on the frame or monocoque, so it didn’t contribute to unsprung weight, but connected the wheels with a sort of telescoping beam axle. It worked reasonably well on front-engine cars, providing low unsprung weight without radical camber changes, but the axle made it impractical for rear-engine designs.
Mercedes adopted the low-pivot swing axle approach, which it called [i]Eingelenkpendelachse[/i]; VW came up with something similar in the late sixties. The low-pivot design, as the name implies, arranges the axle half-shafts so the geometric center of their arc of motion is a single point [i]below[/i] the differential, rather than having each axle pivot at the side of the diff. Doing that has two effects. First, it lowers the roll center, which reduces jacking. Second, it causes the swing axles to act as if they’re much longer than they actually are. By increasing the radius of the arc they transcribe, the change in wheel camber is only a few degrees, rather than 15 or more.
A pure trailing arm suspension is in some ways the opposite of swing axles. The wheels are carried on an arm that hinges to the body ahead of the axle line. The trailing arm allows the wheel to move vertically, but not to change its camber relative to the angle of the body. (As the car leans, the wheel camber still changes, because the arm itself is attached to the body.) Trailing arms don’t induce oversteer, but they tend to produce massive roll understeer instead. With a rear-drive car, however, the axle half-shafts will still influence wheel location unless you have a universal joint on each end of each half-shaft.
That’s essentially what Jaguar and Chevrolet did for the E-Type and Corvette suspensions (and the second-generation Corvair), although they also added additional lateral links to allow camber gain in turns. It worked much better than swing axles (even the low-pivot variety), but it was more expensive, which is why it was slow to catch on.
Incidentally, if Chevy had built the Cadet as Earle MacPherson originally wanted, it would have had independent suspension via struts — like a modern Camry — in 1947. The only reason it didn’t happen was (unsurprisingly) cost.
In the mid 1950′ s way ahead of it’s time, the Maro corp. ( Mid American Research Corp.) with engineers from the original Bantam “Jeep” ( stolen from Bantam and handed to Willys after all developments were finished and initial production began ) developed what was to become the long forgotten M-422 Mighty Mite Jeep type vehicle for the Marine Corps witch had many advanced designs such as 4 point leading and Trailing arm suspension to help prevent inadvertent rollovers. Interestingly the much later ” Hummer “utility Vehicle was to copy a version of this suspension layout after the disasterious M151 “Mutt with rear 2 point early Corvair type suspension.
Also interestingly the newly formed American Motors bought the project and with engineering from the old Hudson division developed A V4 aircooled engine with aluminum block , heads and aluminum cylinders with chrome bores all way ahead of there time.
American Motors did offer an aluminum block for its six-cylinder engine for a while in the early sixties, although take-up was low and my understanding was that the blocks ended up being quite troublesome.
You may want to take a look at one of the GM patents that relate to the second gen Corvair rear suspension. US Patent 3,327,803 describes the late model Corvair IRS. (It does not specifically cite the Corvair, but all the drawings used are of the late model.)
Among the claims is that this implementation provides passive rear steering that in the patent’s words “induce angular change of the plane of driving wheels in an under-steer direction.”
Unfortunately the patent is vague on any actual specifics regarding angles or other dimensions, but that’s to be expected since GM was patenting the concept, not a specific implementation.
That sure does appear to be the second-gen Corvair. Interesting — I had wondered if the lateral links were intended to provide toe control, and the patent asserts that that is indeed their function.
Lancia used semi trailing arms on the Aurelia when it was introduced in 1950. They switched to a DeDion set up in ’54.
Great retrospective. However, you missed one serious design issue on Corvairs. The heater. On both early and late models, the direct heater (which uses air that has circulated past the heated engine and exhaust manifold) is dangerous enough that the largest Corvair aftermarket vendor sells a CO2 monitor/warning alarm. Clearly an engineering concession to cost, this heater does not employ a heat exchanger which would keep potentially poisoned air OUT of the heating system. Nearly every engine blow-by seal can add fumes to the passenger compartment. More insidiously, however, is the possible introduction of combustion exhaust by way of exhaust packing failures and/or head gasket problems.
While I think these cars are terrific, I cannot get past the absolute miserable design of the heating system.
Both of my Corvairs (a ’61 van and a ’62 sedan) have a stock gasoline heater in front of the passenger firewall. The combustion happens outside the cabin and is exhausted under the vehicle. No fumes, no vapors. It heats a lot faster, too.
So don’t heat exchangers exist NOW, that could be placed on all extant corvairs via recall, so NO possibility of monoxide-poisoning could occur?
In 72 I bought a 65 Corsa that had thrown a rod through a cylinder barrel and the crankcase but was still being driven. (!!!).
You can imagine the atmosphere inside the passenger compartment, given the heater arrangement.
As you say, blowby was a near-universal feature of the interior air even without throwing a rod. The pushrods ran in separate tubes between head and crankcase, sealed by o-rings on either end. The ones at the head quickly became brittle and leaky from the heat, which is how the blowby got into the heater air. Silicone replacement o-rings were popular with the cognoscenti.
I owned a 66 Monza with the 110 and a Powerglide during the 1990’s. It was without a doubt the best driving and riding car I have ever owned and I regret selling it. I would like to buy another one, but this time I think I’ll get one with the 140 engine and maybe a manual transmission, though the Powerglide is not a bad transmission.
Not all Corvairs used engine air for heat.
My father and I both owned 1960 model Corvairs. In each vehicle, cabin heat was supplied by a Stewart Warner gasoline fueled heater mounted in the front trunk (even less room for luggage!). These were factory equipment items as evidenced by the their coverage in the official Corvair shop manual.
My 1960 Corvair, my first car, lasted all of 2 months until I totalled it in a rollover. Without the benefit of seatbelts, I walked away with a sore arm from hitting the inside of the driver door.
I later acquired a 1961 Corvair Loadside pickup which was built without a heater (of any kind). However, it was obvious provision had been made in the design for a gasoline heater to be mounted below the dash on the passenger side of the cab. I believe later models of the truck and van utilized engine heat via ducting.
Subsequently, I owned a 1961 model Corvair with a 4 speed manual tranmission, a Corvair passenger van and a 1965 model convertible with the four carb 140 HP engine. All of these vehicles were enjoyable rides.
Thanks for an informative and entertaining article!
Nice article on one of my favorite cars! One small correction, the Astro 1 engine mounted two, three throat carburetors, one for each bank of the flat six. It was proposed in one of the Corvair histories that GM used in-house carb castings with Weber 40IDA3C internals. That carb was used on some Porsche 911s, the 914-6, and early Ferrari Berlinetta Boxers, I believe.
[quote=Stuart Linderman]While I think these cars are terrific, I cannot get past the absolute miserable design of the heating system. [/quote]
If the CO2 alarm goes off, your only recourse is to open the windows until you can fix the leak, right? Doesn’t make me want to run out and get a Corvair!
At some point [i]Consumer Reports[/i] wrote about a man who had reached an out-of-court settlement with GM. He’d driven a Corvair van for some years in his business and suffered serious long-term harm from exhaust fumes. Part of the agreement was that he couldn’t comment publicly, so [i]Consumer Reports[/i] had nothing to report beyond that.
[i]Road & Track[/i] had an article in the late 1960s, when the Corvair was still in production, about what the Corvair should have been, and still could have been if GM had had the corporate desire. This is from memory and therefore sketchy, but they said the Corvair had always been sloppily built, and burned and leaked oil. IIRC, they also suggested a carburetor setup and gave an estimate of the power it would have yielded–less than the turbo’s notional 180 hp, but a realistic rating, unlike the turbo’s.
Some years ago I was flipping through a book for Corvair owners on the news stand, and it made a couple of points that interested me:
1) The mule-drive fan belt was narrower than most fan belts. Owners were cautioned that if they put a generic fan belt on a Corvair, it would ride too high in the grooves and be thrown.
2) In its lifetime a Corvair would leak or burn ~$120 worth of oil. There was no repair for $120 that would put a stop to it, so owners should top up the oil and take it philosophically. This was written before the advent of Viton seals.
In fairness, a great many older cars leak and/or burn substantial amounts of oil, even when they’re in good mechanical health. Most of the Corvair owners to whom I’ve spoken acknowledge that the engine does leak oil, but as mechanical foibles go, it’s hardly egregious. A friend of mine, who is presently restoring a second-generation Corvair, notes philosophically that the oil seepage of his car did at least keep the engine trim from rusting…
[quote=Administrator]The de Dion, which was popular for racing, but used only sporadically on production cars, was not really an independent suspension; it mounted the differential on the frame or monocoque, so it didn’t contribute to unsprung weight, but connected the wheels with a sort of telescoping beam axle.[/quote]
In the early 1970s an issue of [i]Road & Track[/i] had a pull-out suspension supplement, bylined by then engineering editor Ron Wakefield, covering the various kinds of suspensions.
According to the supplement, de Dion suspensions traditionally had a beam axle, but not a telescoping one. The half-shafts would be splined so the rear wheels maintained a constant track as the suspension worked. Wakefield went on to say that the splines (at least in years past) tended to bind, hence the telescoping axle (and no splines) on the Rover P6. Rover accepted the changing track, and some tire scrub, as the tradeoff. Wakefield also said that modern splines didn’t have the binding problem.
The Alfetta of the 1970s was so named because its namesake racer had a de Dion suspension.
That’s a good point — thanks for the clarification. What I was trying to get at was simply that the de Dion tube has to have some provision for limiting track changes.
These come to mind for me:
Karmann-Ghia Type 34
What were the other ones you were thinking of?
Mazda Luce coupe, almost a 1:1 copy.
…Meaning cars whose styling was clearly influenced by the Corvair? I would add:
ZAZ Zaporozhets 966/968
BMW 2000 CS
Few Amercian cars had more impact on automotive styling in the 60s. What other car influenced the Soviets, the French, the Italians, the Brits, the Japanese and the Germans?
The Luce Rotary Coupe was styled by Bertone rather than Mazda’s in-house, but if I dug around I’m sure I could find other Japanese cars that show a Corvair influence.
My 3rd Corvair was a ’65 Corsa convertable w/ the quad-carb 140hp engine and 4 speed manual. I got it seriously sideways at high speed yanking the wheel left to avoid an accident on a 2 lane highway. The heavy rear-engine swung us around into oncoming traffic with me frantically spinning the *slow* steering right-right-right. It eventually righted and we slid onto the left shoulder, more or less straight. As the dust was settling, we noted that BOTH wheel covers from the right side had popped off the rims and were rolling on down the road on their own. I can personally vouch for the suspension improvements in the later Corvairs.
The carburetor float axles were aligned with the longitudinal axis of the car. This meant that in hard cornering the floats would slosh closed or flood the engine. Several contemporary hot-rodding books address this problem including adding balance springs to the floats or rotating the carbs 90deg. I did a little autocrossing in the Corsa and never did get happy with that.
The oil leak/heater thing could be solved with new exhaust gaskets and slathering the pre-viton pushrod tube ‘O’ rings with thick, aluminum based anti-seize compound. It carried away some heat so it couldn’t cook the rubber. Never had a problem with the heater after that.
When I sold the 1st Corvair (a ’64 Monza Spyder, turbo) I took the prospective buyer across the San Mateo Bridge (SF Bay Area), hitting 130mph before the curved riser on the San Mateo end. It was still winding up. He bought it on the spot.
We had a ’62 Monza Coupe 4-spd and a ’65 Corsa coupe 4-spd (both non-turbo, 110 & 140 hp respectively). Both were bought new (the ’62 for $2200; the ’65 for ?? $2500 ??).
The Corsa’s engine would stumble due to flooding on hard right turns, but not on left turns. It would not happen with all the air-filter assemblies removed (with just the bare carbs showing). It took a long time to learn that, and I never did discover why the induction system behaved that way.
The ’62 had all the HD stuff, including sintered iron brake linings. The brakes worked well, but it was impossible to get the rear brakes “balanced” so as to not lock one rear wheel.
Both were great performance values. They were my 5th and 6th consecutive rear-engine cars, including a 1955 Porsche 1500 S (I was its 3rd owner). I did learn how to drive oversteering cars (I’d had two VW’s too). The shorter rebound straps on the ’62 and the double U-jointed half-shafts on the ’65 helped a lot.
Enjoyed your piece – thanks!
Enjoyed your post as well.
They were really fun little cars weren’t they? I did enjoy the occasional Porsche-hunt on Redwood Road between Hayward and Oakland in the SF east bay. Didn’t always catch them but a few were surprised at how well the Corsa did. Loved it.
Umm, the Spyder was not nearly capable of 130 mph. Even the speedometer topped out at 120.
The ’64 Spyder made max. hp at 4,000 rpm. With its 3.55 axle ratio, that equaled exactly 80 mph. Even if you could coax it to 5,000 rpm, that was still only 100 mph. 130 mph would have requited 6,500 rpm, which was well beyond what these were capable of. Most reviews noted that power dropped quickly past its peak power (4,000 rpm), and 5,000 rpm was only barely achievable when shifting for max acceleration.
Sounds like either you had my old 65, or I had yours!
I did the 90 degree carburetor rotation anti-slosh thing because I thought I was a superhot driver who needed it. It put the axes of throttle butterflies on each side in line forward to back inside of parallel side to side, so they just were clamped together and moved simultaneously, no more progressive linkage. The stock linkage was just bent rods through holes, really sloppy.
The other carb problem was that the progressive setup only had idle circuits on the primaries, so if it wasn’t floored frequently enough to open the secondaries, the gas would just sit in the float bowls and evaporate and sludge them up. This was the case with mine when I bought it (who buys a car like this and never opens the secondaries?) so bad I had to junk the secondaries. Replaced them with another pair of primaries with the idle circuits, in addition to the rotation described above. So balancing all 4 carbs with the sloppy linkage was futile.
Another (cheap) “fix” I did was to press copper tubes into the bowl vents to make them a bit taller so fuel wouldn’t slosh out.
The best mod I had was installing steering knuckles with shorter arms on them to make the steering faster, avoiding that slooow steering you mention.
I enjoy the thoroughness of your article and the facts.
I own a 1960 in Bolivia that I have completely rebuilt, and I drive it daily through the mountains enjoying how well it handles.
The Mountains of Bolivia? Wow. A 1960 Corvair would not be my car of choice to tackle the Camino de la Muerte…
The National Automobile Museum in Reno, NV also has a copper-cooled four on display. I think they indicate it is one of only about two surviving in the wild.
really enjoying your various topics you’ve written on.
re- 1960 corvair 4 speeds. engineering did build and test 4 speed transmissions for 1960 corvairs, but it never became a regular production option for that model year, despite a published road test of a 4 speed car in one of the major enthusiast magazines, and many rumors in the press noting it ‘would be available soon’. production of the transmission was close enough that it is included in the 1960 assembly manuals, but is further noted as ‘option cancelled’, and chevrolet zone offices sent letters to dealers explaining "chevrolet central office has advised us that the 4 speed manual transmission for the corvair will not become available for the 1960 model year.’
the 4 speed did go into regular production for the 1961 model year, now with cast iron case and 16 spline mainshaft that was used through the rest of corvair production.
in the early 60’s, corvairs had a higher percentage of 4 speed installations than any other american car short of the corvette.
The corvair society museum in Ypsilanti (part of the heritage trust museum) has a ’60 model prototype 4 speed on display.
corvair society of america
Thanks for the information. I hadn’t assumed the four-speed was available until the start of the ’61 model year in the fall of 1960, but the way the article text was worded was misleading, so I edited it a bit.
The swing axle was sometimes used in Europe and Britain as a cheap way of providing independent rear suspension but like any cost cutting option it had its drawbacks and was controversial over here as well as in America. My personal experience was with the Triumph Herald and Vitesse which handled very well up to a point but if that limit was exceeded the cars would become quite a handful to an experienced driver-the rear wheels would tuck themselves under and the oversteer was alarming and if you applied the brakes when cornering you were really asking for trouble.The Corvair also had the disadantage of the rear engine layout on top of the crude rear suspension.To a nation of people raised on conventional but safe handling cars the rear engined Chevy and its original cheap cost cutting suspension deserves its bad handling reputation.
It was also a victim of mechanical ignorance. The front wheels, with almost zero weight on them, wanted no more than 12-15 lbs of pressure, while the rears needed the usual for the times 25 or so. When ignorant or muleheaded owners put the same 25 lbs into the front tires, they would oversteer insanely.
A similar problem I think led to the death of many Corvairs, which was the mechanical “geniuses” of the time who had never seen aluminum before overtorquing the fasteners and especially spark plugs on the engine and stripping the threads.
Corvair- what memories! My buddy’s parents owned a Corvair and a Lotus Elan (talk about contrast!)- mainly, I remember how, back in the day: 1. the motor of the Corvair was popular as a transplant into VW vans and 2. the motor leaked oil like a sieve, even when compared to contemporary vehicles. My brother has an Austin Healey: no oil leaks whatsover- imagine a BRITISH car engine making a US car motor look bad!
But… the Corvair engine ran clockwise compared to regular Detroit cars which ran counterclockwise, so that they could adapt existing transmission internal gears to the engine being behind the tranny. Whereas VW engines ran the normal counterclockwise, so Corvair engines had to be adapted to run in reverse direction when adapted to a VW. Luckily the fan was symmetrical.
Supposedly the VW trans would be OK if you never used first gear
I have one and luv it.
Its a fun car to drive and always get complements.
FYI: A correction MUST be made about the Copper Cooled Chevy, there is a 1923 Copper Cooler body and cutaway motor (separate) in the Buick Gallery In Flint MI, USA. Please correct this soon.
Fair enough. There are actually several survivors, although not many and not always in one piece. (There’s also an engine in the Heritage Center.)
Thanks for the acknowledgement. If anyone at Flint’s Buick Gallery or any other owner (owner or institution) of a copper cooler (motor or car) reads this, I think they would probably be grateful for their acknowledgement (technically).
Excellent article! I’ve known the story for many years yet your piece added texture and background I haven’t seen before. One comment: You mention that ’65 Greenbriers were “left over” ’64s. I don’t think this is the case there are more than a few differences in the engine and trim that indicate continued development and of course production dates fall in the ’65 model year. In my understanding, the commercial version of the ChevyVan replacement was ready for the ’64 model year but the passenger version, the SportVan was not. Chevrolet decided to keep the Greenbriar (but not the Corvan or Rampside) in production until the SportVan was ready later in the model year.
You’re likely correct on the ’65s. There was also a surprising number of year-to-year engineering changes on the late Corvair passenger cars, particularly considering that development had theoretically ceased. One would assume that after ’65, the cars would all be pretty much the same except for safety and emissions modifications, but in talking to people restoring the second-gen Corvairs, that’s not the case (although a lot of those changes are not reflected in the shop manual!).
Excellent article! Two notes:
The last engine pictured in the article does not in fact have air conditioning. Air conditioned Corvairs had the usual GM 6-cylinder swashplate A/C compressor mounted in the position of the alternator. The alternator was swapped to the opposite side, replacing the idler pulley. Interesting trivia: the compressor was built to run in the opposite direction for the Corvair, and such units were painted green rather than black to distinguish them. Speaking of which, a big advantage of the Gen II Corvair over the ’65-66 Mustang was the fact that the Corvair A/C was completely integrated into the instrument panel, rather than being a hang-on unit. Unfortunately it was not possible to get A/C on the turbocharged Corsa.
One bit of forgotten history you may want to add: The 1966 Corvair was the first production car ever fitted with a front chin spoiler. I wrote about it here:
autouniversum.wordpress.com/ 2013/11/21/ advent-of-the-downforce-inducing-aerodynamic-appendage/
The wind-wander problem associated with rear-engine cars of the period was not actually a direct result of the rear engine location; all cars of the era had huge amounts of aerodynamic lift at the front. However, having a big heavy engine up in the nose largely mitigated the problem. The 1966 Corvair solved the issue by addressing the root cause.
That’s right, I had forgotten! My first mod to my 65 was the front lip from a junked 66!
All Corvair generators and alternators were mounted on the driver’s side of the engine. The a/c compressors were always mounted on the passenger’s side.
The a/c compressors were driven by a belt directly off of the crank pulley.
I had three Corvairs when I was young: a ’62 Spider (turbocharged) that I bought for a song because its turbo had ceased, a ’65 Powerglide sedan that was an acceptable car, and a ’66 Corsa convertible (4 carb) on which I installed Michelin radials, short steering arms (for fast steering), and copper sinterred brake linings. It was like a poor man’s Porsche. The car was very reliable and great fun to drive. I almost bought a similar one on e-bay recently (I think the owner wanted about $12 grand for it) but decided on a TR8 instead. The ’66 had a number of detailed improvements over the ’65.
Almost every year of the Corvair’s run had some significant detail improvements, which can be a little confounding.
You did not mention that Ralph Nader finally got NHTSA to conduct a defect investigation into the first generation Corvair handling and stability. The initial finding, based on testing a fully loaded Corvair found no problem. In fact, according to its first report, the NHTSA engineers could not get the car to roll over. Only later did one of the engineers test a lightly loaded Corvair which immediately rolled. The second report discussed the fact that the primary safety problem with the Corvair was that it understeered up to a lateral acceleration of about 0.3 g, but then changed to violent oversteer in less than 3/4 second — faster than most driver’s reaction time. With the oversteer, the Corvair slid so that it was sideways to its direction of travel, and would easily roll over as its outboard rear wheel tucked under. Unfortunately, there were no good crash statistics at the time that would have documented the number of rollovers that resulted. There is extensive documentation of this story in a Senate report published around 1974.
The NHTSA investigation is indeed mentioned in the article — look at the paragraph below the photo of Ed Cole. I have not read the subsequent Senate report, though, which would be worth a look. Do you have any more details on it?
Along with the having the anti-roll bar as standard from the outset, would the Chevrolet Corvair have benefited from the all-alloy BOP 215 V8 to better equip it against the Ford Mustang V8s (similar to the rear-engined V8s in Tatras)?
I’m going to say probably not. First, while people have certainly installed V-8s (including the Buick 215), the Corvair wasn’t designed for a V-8 or a water-cooled engine and installing one is a pretty elaborate exercise. (The Crown Corvair, q.v., is a fun toy, but not long on practicality.) A production V-8 Corvair would have been cumbersome (and thus expensive) to build and would probably have sacrificed a lot of mechanical commonality with the standard car. On top of that, the aluminum 215 was itself wasn’t cheap to build and Chevrolet would have had to buy the engines from Buick at a markup, making it even more expensive. (That’s one reason Pontiac was so reluctant to use the aluminum 215.)
If you put all that together, it would have been hard for Chevrolet to keep the price down, which would have made the car a tough sell against the Mustang, whose mechanical stuff was all pretty much off-the-shelf. Keep in mind that this is sixties GM, which considered anything under 100,000 units a year to be small beer.
You say that the Doyle Dane Bernbach ad campaign for Volkswagen was a factor in green-lighting the Corvair project in September 1957 but Doyle Dane Bernbach did not get the Volkswagen account until 1959.
Eek, thanks for the correction! I’ve amended the text and am kicking myself for not having caught that before.
SECOND COMMENT: The Corvair 4-speed manual transmission would not take a lot of abuse. Pontiac used a similar transmission for their 4-cylinder Tempest, however they wouldn’t install it behind the aluminum 215″ V-8, nor the 326″ which was optional in 1963. V-8 Tempests had the choice of 3-speed manual or Tempestorque automatic (which was similar to the ‘Vair Powerglide).
The four-speed was originally a low-cost adaptation of the original three-speed, so that’s not surprising. My understanding was that even the Tempest three-speed, which I assume was beefed up a bit for 1963, was marginal with the 326. I recall that Car Life broke a gear of theirs, which if I’m remembering correctly was behind a modestly hopped-up Royal Bobcat 326. Looking at the comparative torque figures, it seems like it was just more than the Corvair transmission was ever designed to take.
I had a friend with a 1964 Corvair (110-hp?) which was supercharged with a Paxton blower, 4-speed transmission and 3.55 Positraction gears. Also, the ‘Vair was fitted with Michelin X steel-belted radial tires. This guy swore it could lift the front wheels off the pavement on acceleration.
The gauntlet was tossed (and I believe money wagered). Our proud Corvair owner nailed the throttle and dumped the clutch…
Next trip was on the back of a tow-truck to the local Chevrolet dealer, being the clutch, pressure-plate, two synchros in the tranny, ring & pinion and Positraction unit were damaged. The service department put everything back together (customer pay).
The fool tried the stunt a second time, with similar results; and I don’t believe the front wheels left the ground THAT time either.
(Methinks the Chevy service department named him a star customer. And I’m not aware of a third attempt.
That’s very funny. You’d think after the first time, he would have learned an important lesson, like considering, “Even if I win this bet, will it be enough to pay for rebuilding the entire drivetrain again?”
The guy was a bit on the strange side. Had some money behind him. Thought the Corvair was: “…the most superior car on the road.” (Then-1966) everyone is entitled to their own opinions. I guess he never drove a Corsa.
They were interesting cars and I “wrenched” on a few as a mechanic; but no desire to own one. Aside from tricky handling (60-64) the steering box was right behind the front bumper and a serious crash would displace the steering mechanism and wheel up and back 18″. Not an indictment on the Corvair as several other makes also placed the box and un-collapse able steering column in the same location.
Big yes on the steering box thing. The thing is that without an engine in front, and without a stub frame to carry the engine, the most frontal solid item in the car was the steering box, so even if you just bumped something at a low speed, the front sheet metal would crumple and the steering wheel would come back and break your nose. Ask me how I found out.
They finally got a collapsible steering column on the 69s.
A major Corvette enthusiast related Chevrolet’s experiments with a mid-engine platform. I believe it had a 327 hooked to an early Pontiac Tempest transaxle. They used the automatic version knowing the 4-speed wouldn’t handle the torque of a 327.
That would make sense, since the 327 had nearly three times the torque of the Corvair engine and over 50% more than the slant-four Tempest, which is a lot to ask of an unmodified or even lightly modified manual transaxle. I assume TempesTorque was more forgiving in that regard, since the direct clutch (which seems like the most obvious failure point) could be beefed up without an extensive transmission makeover. It’s conceivable that TempesTorque also had a higher torque capacity to begin with — I’ve never seen any factory figures for the transaxles — since Pontiac didn’t offer most of the hotter engine options with the three-speed.
ANOTHER FUNNY ‘VAIR STORY: I had a customer with a really cherry ’64 Monza Convertible. Even though it was 10-years-old it was in “like new” condition.
One day he called me up complaining that it was almost impossible to start in the mornings. We arranged for it to sit overnight and I went to work. Long story short, I found a bad electrical connection (they lived near the ocean) and there was no 12-volt “kick” to the coil in the start mode. I finished the tune-up and it instantly started at the first turn of the key.
A couple of weeks later and I happened to run into the owner, with the standard question; “How is your Corvair running?”
Owner replied that I f*cked up… Being I prided myself on quality work, what the???
Seems right after I worked on it it was stolen right out of his garage in the dead of night. It was never recovered. (Methinks it was cut up and made into a dune buggy:-(
CORVAIR OIL LEAKS: I worked in the service department of a large Chevrolet dealer in the late 1960’s. Common places of Corvair oil leaks were 1) push rod tube seals. (Later cured by improved sealing materials). 2) Valve covers. (Cured in ’65 with wider retaining brackets instead of washers and proper torquing.) 3) Oil filler cap and sealing surface on the filler tube becoming distorted by the constant pressure of engine oil whipped up by the crankshaft. 4) Oil pressure switch failure. (This, however, is not limited to Corvairs as many domestics of the era used the same design).
With many years and thousands of miles, heat and vibration can cause many other opportunities for leakage today.
I also remember complaints of burned valves (the Spyder used upgraded (stellite) valves.) Also hydraulic lifter issues. Part of the lifter issues may be due to the oil available then. Today’s lubricants, for the most part, are superior. 93 octane (if available) and a lead additive may help with the valve issues.
I posted this previously but it may have been lost in cyberspace. My apologies on repeating myself.
As I discovered while replacing the crankcase and broken cylinder barrel on the previously mentioned 65 Corsa, the width of the sealing surface between the cylinder barrels and the head was increased between 64 and 65, due to head gaskets failing with the narrower with seals.
“claimed that Chevrolet engineer Frank Winchell actually flipped a Corvair prototype”
Flipping is end over end and very difficult to accomplish, rolling is a sideways motion.
Are you sure you meant flip and not roll?
DeLorean described it as a flip. Lacking more details, or photos/videos, of the alleged incident, I’m loath to second-guess it further. However, the idea that “flipping” can only refer to one specific direction of motion strikes me as unhelpfully and unnecessarily prescriptive. I can envision a variety of scenarios that the average person (and I) would likely describe as flipping sideways or flipping diagonally and that are clearly distinct from a roll. Short of some kind of formal engineering paper or research study where you’re defining very specific categories for some statistical or analytic purpose, that seems a perfectly reasonable colloquial description.
When I was 16 years old I owned a 4 speed 63 Monza 110 HP coupe in 66 that was my first car. It cost about $850 dollard used with less that 35,000 miles on it. I loved it and drove it every where in the Tampa bay area. I would load all my buddies in it and we would chip in and drive to Clearwater beach and all over the Gulf beaches for $3 dollars worth of gas from the north Tampa Area near Bush gardens. We would road race our buddies around the University of South Florida’s roads which were not built up and sparsely populated back in the mid 60’s. It was defiantly my Poor Mans Porsche. I loved to drive it fast and broad slide it on the many dirt roads that still existed then and even through the many Orange Groves in the area. There was this dirt oval of sorts around this pond in the woods near the USF area that we called the Duck Pond that people would bring their old stock cars, dune buggies and jeeps out to race each other. It was wild, the police never bothered us and I cant believe no one ever got hurt to my knowledge. I let one of my close friends drive my prized Corvair around the Duck Pond oval going faster and faster until he went the wrong way around this dead tree that was just past one corner that had a ditch across the path that bottomed the suspension and shoved the engine back into the cross member behind the crank pully snapping off the oil filter housing and dumping oil all over the engine and the dirt track that we were racing on. so now I am broke down out in the middle of these woods with no oil in my engine and how am I going to have to tell my dad that this happened ? I got towed home by one of my friends who was also there and the next day I bought a new oil filter housing piece from Dempsey Chevrolet in Tampa for about $4 dollars and changed it out.
I kept it until 1969 when I traded it in for a brand new $2500 dollar Opel Cadet Rallye because the Corvair had a screwed up starter gear on the engine that ate up the gear on the starter in no time that required pulling the engine and replacing the clutch and pressure plate that the starter ring gear was attached to. I had to push start that car or park it on inclines and let it roll backward and start it in reverse or roll it going forward. I had few tools then and my mom hated me working on my car in our car port where we lived so I traded it for the Opel. It cost me $65 dollars a month to finance back in 1969. Some day I will write about the 66 4 door power glide hard top that was given to me about 20 years later when I was doing car repairs that I moved away and left behind at my old place because I had no help and way to move it to my new shop after having moved about a dozen other cars of mine that did not drive but ran that I had some help with moving. I still miss both of them more than about any other cars that I have ever owned.
What is the story behind Peter Brock’s Isetta (later Beetle) challenging rear-engined 2-seater 1956 GM Cadet concept and the potential role it played in the development of the Chevrolet Corvair?
The 1956 Cadet concept featured a 67-inch wheelbase, was to be powered by theoretical an air-cooled 2-cylinder (not sure it is was an Inline or Boxer layout) and priced at $1000, being similar to the BMW 700 yet slightly smaller with a lengthened (possibly 4-seater?) version being considered at one point as a challenger for the VW Beetle and Renault Dauphine.
GM rejected the project, only to later resurrect it with the project eventually evolving into the Corvair.
Also where can I find out more about the Chrysler A-106 project?
According to the account on Brock’s company website, the rear-engine Cadet was a styling exercise Brock did with encouragement from Harley Earl (whose name the BRE website curiously misspells). While a full-size model was built — there’s a photo of Brock sitting in it — I don’t know that it had any powertrain in other than a hypothetical sense. Since the project came from Styling (and I think one of the corporate Advanced studios at that), I doubt it.
I think its connection to the Corvair was probably close to nil. Chevrolet’s advanced engineering group was already pursuing the air-cooled/rear-engine layout, and had been even when Styling first hired Brock; it was a pet project of Ed Cole’s. The Cadet concept doesn’t seem like anything Chevrolet would have seriously considered building in the mid-fifties, not least because the $1,000 price point was even less realistic than it had been for MacPherson’s Cadet project a decade earlier. The mini-Cadet was a cute concept, but I’m pretty sure that’s all it was.
An important thing to remember about GM in that era is that it was enormous and had lots of largely autonomous divisions and departments that were really quite separate in an organizational and operational sense. Many of them were involved in various sorts of experimental projects, many of which were far removed from any immediate likelihood of production and which were in many cases separate from one another. Of course, some ideas and concepts did pass interdivisionally (the 1963 Buick Riviera is a good example), but many did not, and I think in a lot of cases, the left hand didn’t talk to the right. However, looking at it from outside and in retrospect, it’s easy to presume connections or cohesion that didn’t necessarily exist.
I see. The mini-Cadet concept of 1956 immediately brought to mind the notion by some of GM at one point looking at a family of downscaled rear-engined versions of the Corvair concept, based on how the Corvair’s Flat-Six engine either was from the outset or became a modular design capable of spawning a Flat-Twin or Flat-Four at one end to a Flat-Ten or Flat-Twelve at the other end.
Would a version of the small 1956 Cadet concept have been more suitable had it been produced in the UK or Germany, especially since Opel were developing a 700cc version of what became the Opel OHV engine?
The closest equivalent that GM in Europe seemed to have looked at is the front-engined FWD Vauxhall XP-714 project after the Mini appeared.
Do any images exist for the Chrysler A-106 prototype?
Had the rear-engine Cadet been developed by or for Vauxhall or Opel, it might have had marginally more production potential, but it appears to just been a Styling experiment that Harley Earl happened to think was neat. (I’m not entirely clear what studio Brock was in during his brief stint at GM Styling, but I gather it was one of the experimental studios, which would make sense given his very young age and lack of experience or seniority. Production-track designs were something I think you had to sort of work up to doing.)
The Corvair was not a corporate project, it was a Chevrolet project — a significant distinction in those days. Had it been the brainchild of one of the corporate Engineering Staff groups, they might have tried to make it a modular engine design, if only to see if there were patents they could secure in that realm. As far as I know, making a modular engine wasn’t part of the brief for what became the Corvair. Robert Benzinger, who did a lot of the engine development work, said that they settled on the flat-six layout pretty early on and had quite a struggle getting that to work. One very significant point Benzinger makes in that regard is that with an air-cooled automotive engine, the differences between an H-4 and an H-6, and presumably an H-6 and multi-cylinder variations, are not trivial and are a lot more involved than just adding or removing cylinders from a liquid-cooled inline engine.
On the Chrysler A-106, I’ve been pondering that. I don’t specifically recall if I’ve seen any published photos of the earlier iterations. There may be some in the Collectible Automobile article on the early Valiant and thus in the HowStuffWorks.com article (many of their automotive articles are repackagings of earlier CA pieces).
Managed to find some info on the Chrysler apparently it was to feature a Flat-4 engine of as yet unknown displacement and power.
There was also the two Chrysler Cadet projects, the first developed in parallel to A-106 and the second during the early 50s though am not sure what engines were to feature in both projects.
Both Ford and Chrysler wrestled with the question of whether to use a four or a six, eventually settling on the six. (Chevrolet apparently did as well, although it appears they settled on the air-cooled six for the Corvair very early on.) I’m sure from the standpoint of everywhere else in the world, it looked like complete madness: “We must economize! Absolutely NO more than 3 liters displacement!” It was not without reason — fuel wasn’t that expensive, only a few states used taxable horsepower-based registration fees, and Detroit assumed that Americans felt the same way about using the gearbox as they felt about visiting the dentist — but it does provide some hints about why U.S. automakers later struggled so badly coming up with decent C-segment cars.
I can vouch for the improved ’64 rear suspension anti-camber spring. As a fearless (stupid) 17 year old I loved to hear the rear wheels (worn bias plies) squeal around long bends. Once…and only once, they did break loose and I found myself doing a 180, smashing flat against the curb and the passenger side rear tire/wheel smashing square on a steel sewer drain. The impact separated the tire from the rim but the spring/shock kept things from caving in and possibly tipping the car. The car landed (on all 4 wheels) up and over the curb, on the grass. All my graduation money went to fixing the car but I did learn something about the car’s limits.
i have a 61 monza coupe here in australia,one of a dozen orso imported into australia for evaluation by g.m.holden from 1960 to 64.
While rear-engined XP-892 was apparently designed around the 4-cylinder Chevrolet 153 engine, what engine would it have likely used had it been signed off for production?
Seems any 6-cylinder let alone a flat-6 was completely out of the question for XP-892, which leaves either the Chevrolet 2300 (along with possible Cosworth Twin-Cam) or the stillborn Vega OHC L-10 (which was love to see specs of) and the 150 hp GM Rotary engines.
I have no idea. The XP-892 was a corporate advanced project, not a divisional one, so while Dick Langworth describes the design as a production-ready one, I think that just means it was not a wild show car concept never intended for human occupation. My assumption is that it was mostly just a pet project for Ed Cole.
Understand. Not sold on the Rotary (as others suggest it was intended for XP-892) though quite like the idea of XP-892 using the Chevrolet 2300 or Vega OHC L-10, especially if either utilized turbocharging.
Would have been interesting though if GM were able to come to a deal with Rover / BL for supply or some of the intellectual rights of the all-alloy Rover V8 (e.g. permitted to revive the slightly different 215 Oldsmobile V8), if not able to buy back the Rover V8. However doubt it would have been able to fit into XP-892.
Is it known whether XP-892 was a 2-seater or a 2+2?
I’m not at all sure that GM would have needed to buy back the rights to the aluminum V-8 if they’d wanted to start using that engine again. They continued using direct derivatives of it, so barring some specific evidence to the contrary, I assume Rover bought a manufacturing license rather than sole rights. The reason GM never returned to it was that Buick, Oldsmobile, and Pontiac decided it was too expensive and troublesome to be worth the bother; John Thornley said the GM execs he spoke with were always amazed that British Leyland were still interested in what GM considered a cast-off dead end.
In any event, the XP-892 was definitely a 2+2 and is explicitly identified as such in some of the design studies.
Page three reads “The half-shafts, now pivoted at both ends, acted as lower control arms while two lateral links acted as upper arms.”
It should be “The half-shafts, now pivoted at both ends, acted as upper control arms while two lateral links acted as lower arms.”
Whoops, you’re absolutely right. (I don’t know how I’ve kept missing that.) I’ve amended the text — thanks!
One minor nit — the second gen turbocharged engine was factory rated at 265 lb-ft torque, not the 232 you list. (See shop manuals, GM published “engine output curves” and the AMA Specifications.)
And you may wish to reexamine the Chevrolet internal decisions in 1964 and 1965 regarding the relationship of the Corvair, Camaro and Mustang. There is significant evidence that GM/Chevrolet were seriously considering making the second generation Corvair a two year model and introducing a third generation Corvair in 1967 that directly compete with the Mustang. That third generation Corvair would no longer be rear-engined (or air cooled) and of course share components with the rest of the Chevrolet line-up.
Of course, when Mr. Nader’s book came out in the summer of 1965, that spelled the end of the Corvair name and the marketing department would never allow using it on a new model car.
The upshot of that was that the car that would have become the third generation Corvair became a separate line, the Camaro instead. And Chevrolet/GM made the decision to continue to sell the rear-engine Corvair from 1967 – 1969 was made in an effort to prove Mr. Nader wrong; cancelling the Corvair at that point might have provided unwanted credence to Mr. Nader (and the various law suite’s) claims that the vehicle was defective.
Chevrolet’s marketing of the Camaro has no reference what-so-ever of any derivation from any previous Chevrolet, let alone the Corvair. They claimed it to be a completed “clean sheet” design.
Thanks for the catch on the torque output. The 232 lb-ft figure was quoted in Motor Trend‘s early road test of the turbocharged second-generation car. Normally, specs like that come straight from the press kit, but several other early second-gen press reports list “N/A” for the torque output of the turbocharged Corsa engine, which implies to me that the 232 lb-ft number may have been either an early estimate or based on the ’64 Spyder engine. In any case, it was subsequently stated as 265 lb-ft, as you note.
The text already mentions that work had been done on a third-generation car (although I clarified some minor points). This of course was completely normal procedures; given the lead time involved, it was customary for designers and engineers to be working on future versions even before the current car went on sale. The full-size clay of the initial styling concept, the XP-849, was finished weeks after the official decision to freeze engineering development.
Here is where things get confusing: Work continued on that project for quite a while afterward, but it was transferred from the division to the corporate Research Studio, presumably at the behest of Ed Cole, who had just been promoted. There was indeed work on a front-engine design, the XP-873, and also a subsequent rear-engine concept, the XP-892, but they were not Chevrolet Division internal projects and they were developed after the first-generation Camaro was already done (the XP-873 full-size model was finished circa March 1967, the XP-892 a year later). So, it was not that the Corvair became the Camaro, but that there were parallel corporate projects that considered some similar directions. (There’s an overview of this topic, with lots of photos, in the April 1982 issue of Special Interest Autos.)
From Chevrolet’s internal perspective, the ’67 Camaro had only a very tangential connection with the Corvair. One could certainly argue that the Camaro filled the same role as the Corvair Monza/Spyder/Corsa, but that was already something of a departure from the original Corvair concept (a relatively inexpensive sporty coupe rather than a compact economy car), and given the Corvair’s bad press, it’s easy to see why Chevrolet marketing wouldn’t have wanted to encourage that idea.
Prior to the multi-link suspension of the Porsche 993, is it known which mass produced rear-engined cars (as opposed to rear-engined sportscars) featured the most ideal suspension layout in terms of mitigating the drawbacks of the RR layout and possessing more neutral handling?
The same goes for rear-engined mass production cars that were more balanced in terms of weight distribution and had less rear-end bias partly as a result of a lightweight engine.
It has been said the RR (technically RMR) Rootes Swallow prototype’s MacPherson strut front and Imp-like rear suspension had very neutral handling.
While have seen people cite the likes of the Hillman Imp, Renault R8, Skoda Estelle (and Garde/Rapid), Simca 1000, Suzuki Whizzkid and others. With others bringing up the 2nd gen Chevrolet Corvair or claiming the pre-993 Porsche 911 arguably possessed the best suspension reputation with their notorious reputation being overblown.
Even though the RR layout fell out of fashion for mass production cars before being temporarily revived by the likes of the Tata Nano and Renault Twingo / Smart Forfour, am fascinated by the idea of which carmakers potentially came the closest to mitigating the drawbacks of the layout with regards to suspension and lightweight engine.
In principle, I would say the second-generation Corvair. I say “in principle” insofar as there were other RR cars that may have generated greater cornering power or had more determined failsafe understeer, but in terms of layout, the ’65 Corvair was the better approach, reducing unsprung weight and allowing for camber gain without radical camber change in extremis and including provision for both track changes and toe control. It would have been better yet if it had not used the halfshaft as a control arm at all, since doing that inherently creates the potential for jacking, but it was a workable compromise. The main drawback was that it was a complex and costly approach for what GM and a good swath of the public still considered an economy car, which I assume also limited its interest to the Rootes group, Renault, et al.
Of course, neutrality of handling is only one consideration. Another consideration was providing a comfortable ride in a small car with limited sprung weight. There’s also an important distinction between steady-state terminal handling and transient conditions. With the original Corvair design, for example, the front anti-roll bar would have provided a fair degree of neutrality in the former state, but would not have completely eliminated the undesirable jacking conditions in the latter.
Regarding pre-993 Porsche designs, I am always suspicious of the auto enthusiast cant that some fundamental flaw is no real problem “if you know what you’re doing.” Part of the mystique of the 911 was that learning to avoid its handling flaws was flattering, a testament to the driver’s skill and knowledge. However, while learning precisely how far and how long you can stick your hand in the alligator tank without getting your fingers bitten off may also be flattering, it doesn’t alter the presence or potential lethality of the alligator in the tank.
The NSU 1000 had a transverse air-cooled engine tilted slightly forward. Weight distribution was 45/55. Suspension was A-arms front, semi-trailing arms rear.
How does the NSU 1000 compare to similarly sized European and Japanese rear-engined 4-cylinder rivals in terms of suspension and weight distribution?
Additionally even though the following is largely down to individual preferences, what would be the ideal suspension layout combo for a smaller rear-engined 4-cylinder car?
Some have also brought up the Volkswagen Type 4 and Brazilian Volkswagen Variant II as a possible benchmark in terms of suspension layout for a rear-engiend car prior to the Porsche 993 (also read of a BMW 700-derived 1967 BMW 1000 prototype that was equipped with a 42 hp 992cc OHC engine from the Glas 1004).
Heard some claim the NSU 1000’s was originally conceived as a 1.5-litre air-cooled engine yet there appears to be some confusion between the former and the K70, which utilized a larger water-cooled development of the air-cooled engine.
A static weight distribution of 45/55 is, to my knowledge, significantly less tail-heavy than the RR norm. In fact, I’m not sure that having less than 55% of the static weight on the drive wheels would be desirable even if it were possible. (For FF or RR cars, 60/40 or 40/60 is generally considered optimal for traction without turning the car into a sledgehammer.)
“Ideal” is a qualitative rather than quantitative metric in this regard because it really comes down to priorities. From a ride and handling standpoint, double wishbones or multilink (using the halfshafts only to deliver power, not to locate the rear wheels) are going to be best, but they’re expensive, heavy, and take up a lot of space, none of which is desirable in a tiny economy car. Swing axles are simple and cheap, but obviously can produce some rather dire handling characteristics. Semi-trailing arms are also relatively simple, cheap, and robust, but they present their own handling problems because they allow toe changes as wheel camber changes. There are some less-usual variations with transverse leaf springs and so forth, and depending on the engine layout, you might even fit a De Dion rear end that would avoid all of the jacking and camber change issues, but they aren’t necessarily dynamically optimal (and a De Dion axle may present packaging problems). The second-generation Corvair approach — trailing arm, halfshaft, control arm, toe-control link — or a Chapman strut are probably reasonable compromises if the cost isn’t too prohibitive.
Reputedly it seems only the Renault R8 at least in Gordini (if not regular spec) spec offers slightly better weight distribution at 46/54, quite surprised about the Imp’s 42/58 figure given the engine apparently weighs 176 lbs / 80kg, while the Simca 1000 as well as the Skoda 120 were claimed to be 35/65 and 38/62 respectively.
Basically am wondering what it would have taken for a regular rear-engined car in the West to end up possessing a similar level of longevity as the Porsche 911 without being a sportscar as such, despite the engine layout being outdated (even with ideal suspension and close to or near 50/50 weight distribution partly via by ultralight engines) short of being produced in the Eastern Bloc?
The more recent Renault Twingo / Smart ForFour also possesses a 45/55 weight distribution, with some assuming a near 50/50 figure being possible in a slightly larger rear-engined car utilizing downsized lightweight engines even if it is not necessarily desirable.
Again, I need to emphasize that for a RR car, 50/50 static weight distribution is not necessarily better. Two objects for RR layouts were to provide good winter traction by placing the powertrain over the drive wheels and to shift weight off the nose to provide easier steering without power assistance. Obviously, extreme tail-heaviness can produce undesirable dynamic effects, but shifting too much weight forward isn’t desirable either.
In answer to your speculation, it depends how you’re defining “the West,” and in any event, the answer has very little to do with details of suspension layout or weight distribution, particularly if you’re talking about vehicles not marketed specifically as sports cars. One of the biggest obstacles to acceptance of RR cars in Western Europe, the U.S., and eventually Japan was a consumer preference (and eventually a regulatory one) for water cooling, which is cumbersome with RR or MR layouts. Another obstacle, particularly in the U.S., was packaging. For an MR or RR layout to work really well, the powertrain needs to be tailored for the layout, which requires either a bespoke engine and transaxle and/or some very clever adaptations of existing ones (in the manner that Chevrolet was able to adapt Powerglide to fit the Corvair), using expensive materials like aluminum. An RR layout also limits your ability to introduce new engines or transmissions into an existing model. If you want to offer more power than can be had by changes of carburetion and modest displacement expansion, you have to resort to more exotic tricks like turbocharging, which again is costly.
By contrast, an FR layout makes it relatively easy to drop a four, a six, or a V-8 in the same chassis and offer a range of transmissions with minimal engineering changes; you can also share the same drivetrain hardware with other FR cars in the line, which RR layouts don’t easily facilitate. Although RR models were commonly small economy cars, they were not necessarily economical to build, at least not on the terms an accountant at GM in the ’60s would consider.
There are also a lot of other, harder-to-quantify considerations, like the negative image created by the association with small, cheap economy cars and even concerns about safety. (In real terms, having the engine ahead of the cabin is not safer in a frontal impact, but you’d have a real argument trying to convince the average punter of that.)
So, the kind of incremental dynamic considerations you’re talking about were really very secondary considerations. Certainly, a reputation for treacherous handling, deserved or not, doesn’t help, but even without such a reputation (or where it’s less of am embarrassing public spectacle), there are a lot of practical downsides to rear engines that shifting a few percentage points of static weight forward does not address at all.
“It would have been better yet if it had not used the halfshaft as a control arm at all ….”
The Jaguar E-type also used the halfshaft as a control arm. I assume this was less of an issue because the E-type wasn’t tail-heavy, because of other differences in the suspension geometry, or both of the above?
It’s not a weight balance issue, but one of geometry. Any time you use the halfshaft as a locating member, there’s a danger of jacking, where the halfshaft acts as a lever against the differential. With a pure swing axle, the potential for jacking is high; a multilink arrangement like the E-type’s or the layout used on the Corvair and Corvette reduces but doesn’t completely eliminate it. (It’s a function of roll centers and the relative positions of the wheel hub and the inboard U-joint.)
I wasn’t able to find any specifics in an online search, but I seem to recall that Bunkie Knudsen’s niece lost an arm in a crash involving a Corvair. If this is true, then the statement that she was injured is true–as far as it goes.
John DeLorean (in On a Clear Day You Can See General Motors) said Knudsen’s niece was “brutally injured” in an accident in a Corvair, although he doesn’t offer any specifics. I’ve also heard the lost-arm story, but I haven’t attempted to verify it.
The Corvair driver who lost an arm in an accident was not Bunkie Knudsen’s niece. Rose Pierini of Santa Barbara, California, had her arm severed when her Corvair flipped. She later settled with GM for $70,000. This case was included in Ralph Nader’s book.
Thanks for the correction — I removed that sentence from the text. (It was how DeLorean described her, but I assume this was a case of misremembering information received second-hand.)