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Monday, May 12, 2025

Sunroof

Sunroof (pronounced suhn-roof)

(1) A section of an automobile roof (sometimes translucent and historically called a moonroof) which can be slid or lifted open.

(2) In obstetrics, a slang term used by surgeons to describe the Caesarean section.

1952: A compound word, the construct being sun + roof.  Sun was from the Middle English sonne & sunne, from the Old English sunne, from the Proto-West Germanic sunnā, from the Proto-Germanic sunnǭ, from the primitive Indo-European shwen-, oblique of sóhw (sun).  The other forms from the Germanic included the Saterland Frisian Sunne, the West Frisian sinne, the German Low German Sünn, the Dutch zon, the German Sonne and the Icelandic sunna.  The forms which emerged without Germanic influence included the Welsh huan, the Sanskrit स्वर् (svar) and the Avestan xᵛə̄ṇg.  The related forms were sol, Sol, Surya and Helios.  Roof was from the Middle English rof, from the Old English hrōf (roof, ceiling; top, summit; heaven, sky), from the Proto-Germanic hrōfą (roof).  Throughout the English-speaking world, roofs is now the standard plural form of roof.  Rooves does have some history but has long been thought archaic and the idea there would be something to be gained from maintaining rooves as the plural to avoid confusion with roof’s the possessive never received much support.  Despite all that, rooves does seem to appear more than might be expected, presumably because there’s much more tolerance extended to the irregular plural hooves but the lexicographers are unimpressed and insist the model to follow is poof (an onomatopoeia describing a very small explosion, accompanied usually by a puff of smoke), more than one poof correctly being “poofs”.  In use, a poof was understood as a small event but that's obviously a spectrum and some poofs would have been larger than others so it would have been a matter of judgement when something ceased to be a “big poof” and was classed an explosion proper.  Sunroof is a noun (sometimes hyphenated); the noun plural is sunroofs.

1973 Lincoln Continental Mark IV with moonroof.

Sunroofs existed long before 1952 but that was the year the word seems first to have been adopted by manufacturers in Detroit.  The early sunroofs were folding fabric but metal units, increasingly electrically operated, were more prevalent by the early 1970s.  Ford, in 1973, introduced the word moonroof (which was used also as moon roof & moon-roof) to describe the sliding pane of one-way glass mounted in the roof panel over the passenger compartment of the Lincoln Continental Mark IV (1972-1976).  Moonroof soon came to describe any translucent roof panel, fixed or sliding though the term faded from use and all such things tend now to be thought sunroofs.

Open (left) and shut (centre) case: 1976 Lincoln Continental Mark IV (right) with Moonroof.

According to Ford in 1973, a “sunroof” was an opening in the roof with a sliding hatch made from a non-translucent material (metal or vinyl) while a “moonroof” included a hatch made from a transparent or semi-transparent substance (typically then glass).  The advantage the moonroof offered was additional natural light could be enjoyed even if the weather (rain, temperature etc) precluded opening the hatch.  A secondary, internal, sliding hatch (really an extension of the roof lining) enabled the sun to be blocked out if desired and in that configuration the cabin’s ambiance would be the same whether equipped with sunroof, moonroof or no sliding mechanism of any kind.  Advances in materials mean many of what now commonly are called “sunroofs” are (by Ford’s 1973 definition) really moonroofs but use of the latter term is now rare.

Lindsay Lohan standing through a sunroof: Promotional photo-shoot for Herbie Fully Loaded (2005).

Unlike many manufacturers, for many years Volkswagen maintained specific “Sunroof” models in the Beetle (Type 1) range.  When in 1945 the British military occupation forces assumed control of the Volkswagen factory and commenced production of civilian models (those made since 1938 delivered almost exclusively to the German armed forces or Nazi Party functionaries), one of the first organizational changes was to replace Herr Professor Ferdinand Porsche’s (1875–1951) internal type designations with a new set and these included the 115 (Standard Beetle Sunroof Sedan (LHD (left-hand drive)), 116 (Standard Beetle Sunroof Sedan (RHD (right-hand drive)), 117 (Export Deluxe Beetle Sunroof Sedan (LHD) & Export Deluxe Beetle Sunroof Sedan (RHD).  The original sunroof was a folding, fabric apparatus and this remained in use until 1963, a steel, sliding (manually hand-cranked) unit was fitted after the release of the 1964 range.  The Beetle used in the original film (The Love Bug (1968)) was a 1963 Sunroof Beetle; at the time they were readily available at low cost but by 2004-2005 when Herbie: Fully Loaded was in production, they were less numerous and some of those used in the filming were actually 1961 models modified (to the extent required in movies) for purposes of continuity.  Interestingly, the one which appears in most scenes appears to be a 1964 model which implies the folding sunroof was at some point added, not difficult because the kits have long been available.

Caesarean section post-operative scar: C-section scar revision is now a commonly performed procedure.

Manufacturers in the 1970s allocated resources to refine the sunroof because, at the time, the industry’s assumption was the implications of the US NHTSA's (National Highway Traffic Safety Administration) FMVSS (Federal Motor Vehicle Safety Standards) 208 (roll-over protection, published 1970) fully would be realized, outlawing both convertibles and hardtops (certainly the four-door versions).  FMVSS 208 was slated to take effect in late 1975 (when production began of passenger vehicles for the 1976 season) with FMVSS 216 (roof-crush standards) added in 1971 and applying to 1974-onwards models.  There was a “transitional” exemption for convertibles but it ran only until August 1977 (a date agreed with the industry because by then Detroit’s existing convertible lines were scheduled to have reached their EoL (end of life)) at which point the roll-over and roof-crush standards universally would be applied to passenger vehicles meaning the only way a “convertible” could registered for use on public roads was if it was some interpretation of the “targa” concept (Porsche 911, Chevrolet Corvette etc), included what was, in effect a roll-cage (Triumph Stag) or (then more speculatively), some sort of device which in the event of a roll-over would automatically be activated to afford occupants the mandated level of protection and Mercedes-Benz later would include such a device on the R129 SL roadster (1998-2001).  Although in 1988 there were not yet “pop-ups” on the internet to annoy us, quickly the press dubbed the R129’s innovative safety feature a “pop-up roll bar”, the factory called the apparatus automatischer Überrollbügel (automatic rollover bar).  It was spring loaded and pyrotechnically activated, designed fully to deploy in less than a half-second if sensors detected an impending rollover although the safety-conscious could at any time raise it by pressing one of the R129’s many buttons.


Alternative approaches (partial toplessness): 1973 Triumph Stag in Magenta (left) and 1972 Porsche 911 Targa in silver (right).  The lovely but flawed Stag (1970-1977) actually needed its built-in roll cage for structural rigidity because it's underpinnings substantially were unchanged from the Triumph 2000 sedan (1963-1977) on which it was based.

Despite the myths which grew to surround the temporary extinction of convertibles from Detroit’s production lines, at the time, the industry was at best indifferent about their demise and happily would have offered immediately to kill the breed as a trade-off for a relaxation or abandonment of other looming safety standards.  As motoring conditions changed and the cost of installing air-conditioning fell, convertible sales had since the mid-1960s been in decline and the availability of the style had been pruned from many lines.  Because of the additional engineering required (strengthening the platform, elaborate folding roofs with electric motors), keeping them in the range was justifiable only if volumes were high and it was obvious to all the trend was downwards, thus the industry being sanguine about the species loss.  That attitude didn’t however extend to a number of British and European manufacturers which had since the early post-war years found the US market a place both receptive and lucrative for their roadsters and cabriolets; for some, their presence in the US was sustained only by drop-top sales.  By the 1970s, the very existence of the charming (if antiquated) MG & Triumph roadsters was predicated upon US sales.


High tech approach (prophylactic toplessness): Mercedes-Benz advertising for the R129 roadster (in the factory's Sicherheitsorange (safety orange) used for test vehicles).

The play on words uses the German wunderbar (“wonderful” and pronounced vuhn-dah-baah) with a placement and context so an English speaking audience would read the word as “wonder bar”; it made for better advertising copy than the heading: Automatischer Überrollbügel.  This was a time when the corporate tag-line Engineered like no other car” was still a reasonable assertion.  It had been the spectre of US legislation which accounted for Mercedes-Benz not including a cabriolet when the S-Class (W116) was released in 1972, leaving the SL (R107; 1971-1989) roadster as the company’s only open car and it wasn’t until 1990 a four-seat cabriolet returned with the debut of the A124. 

Chrysler was already in the courts to attempt to have a number of the upcoming regulations (focusing on those for which compliance would be most costly, particularly barrier crash and passive safety requirements) so instead of filing their own suit, a consortium of foreign manufacturers (including British Leyland & Fiat) sought to “append themselves” to the case, lodging a petition seeking judicial review of roll-over and roof-crush standards, arguing that in their present form (ie FMVSS 208 & 216), their application unfairly would render unlawful the convertible category (on which the profitability of their US operation depended).  A federal appeals court late in 1972 agreed and referred the matter back to NHTSA for revision, ordering the agency to ensure the standard “…does not in fact serve to eliminate convertibles and sports cars from the United States new car market. The court’s edit was the basis for the NHTSA making convertibles permanently exempt from roll-over & roof crush regulations.  That ensured the foreign roadsters & cabriolets lived on but although the ruling would have enabled Detroit to remain in the market, it regarded the segment as one in apparently terminal decline and had no interest in allocating resources to develop new models, happily letting existing lines expire.

The “last American convertible” ceremony, Cadillac Clark Street Assembly Plant, Detroit, Michigan, 21 April 1976.

One potential “special case” may have been the Cadillac Eldorado which by 1975 was the only one of the few big US convertibles still available selling in reasonable numbers but the platform was in its final years and with no guarantee a version based on the new, smaller Eldorado (to debut in 1978) would enjoy similar success, General Motors (GM) decided it wasn’t worth the trouble but, sensing a “market opportunity”, promoted the 1976 model as the “Last American convertible”.  Sales spiked, some to buyers who purchased the things as investments, assuming in years to come they’d have a collectable and book a tidy profit on-selling to those who wanted a (no longer available) big drop-top.  Not only did GM use the phrase as a marketing hook; when the last of the 1976 run rolled off the Detroit production line on 21 April, the PR department, having recognized a photo opportunity, conducted a ceremony, complete with a “THE END OF AN ERA 1916-1976”) banner and a “LAST” Michigan license plate.  The final 200 Fleetwood Eldorado convertibles were “white on white on white”, identically finished in white with white soft-tops, white leather seat trim with red piping, white wheel covers, red carpeting & a red instrument panel; red and blue hood (bonnet) accent stripes marked the nation’s bicentennial year.

The “last American convertible” ceremony, Cadillac Clark Street Assembly Plant, Detroit, Michigan, 21 April 1976.

Of course in 1984 a convertible returned to the Cadillac catalogue so some of those who had stashed away their 1976 models under wraps in climate controlled garages weren’t best pleased and litigation ensued, a class action filed against GM alleging the use of the (now clearly incorrect) phrase “Last American Convertible” had been “deceptive or misleading” in that it induced the plaintiffs to enter a contract which they’d not otherwise have undertaken.  The suit was dismissed on the basis of there being insufficient legal grounds to support the claim, the court ruling the phrase was a “non-actionable opinion” rather than a “factual claim”, supporting GM's contention it had been a creative expression rather than a strict statement of fact and thus did not fulfil the criteria for a “deceptive advertising” violation.  Additionally, the court found there was no actual harm caused to the class of plaintiffs as they failed to show they had suffered economic loss or that the advertisement had led them to make a purchase they would not otherwise have made.  That aspect of the judgment has since been criticized with dark hints it was one of those “what’s good for General Motors is good for the country” moments but the documentary evidence did suggest GM at the time genuinely believed the statement to be true and no action was possible against the government on several grounds, including the doctrines of remoteness and unforeseeability.

Ronald Reagan (1911-2004, US president 1981-1989). in riding boots & spurs with 1938 LaSalle Series 50 Convertible Coupe (one of 819 produced that year), Warner Brothers Studios, Burbank California, 1941.  

LaSalle was the lower-priced (although marketed more as "sporty") "companion marque" to Cadillac and a survivor of GM's (Great Depression-induced) 1931 cull of brand-names, the last LaSalle produced in 1940.  Mr Regan remained fond of Cadillacs and when president was instrumental is shifting the White House's presidential fleet to them from Lincolns.  Although doubtlessly Mr Reagan had fond memories of top-down motoring in sunny California (climate change not yet making things too hot, too often for them to be enjoyed in summer) and was a champion (for better and worse) of de-regulation, it's an urban myth he lobbied to ensure convertibles weren't banned in the US.  

Following Lindsay Lohan's example: President Xi standing through a sunroof, reviewing military parade in Hongqi L5 state limousine, Beijing, 2019.

The highlight of the ceremonies marking the 70th anniversary of the founding of the People's Republic of China (PRC) was the military parade, held in Beijing on 1 October 2019.  Claimed to be the largest military parade and mass pageant in China's 4,000-odd year history (and the last mass gathering in China prior to the outbreak in Wuhan of became the COVID-19 pandemic), the formations were reviewed by the ruling Chinese Communist Party’s (CCP) General Secretary Xi Jinping (b 1953; paramount leader of the PRC since 2012).  The assembled crowd was said without exception to be “enthusiastic and happy” and the general secretary's conspicuously well-cut Mao suit was a nice nostalgic touch.

Two generals of the Belarus army take the salute standing, in Honggi L5 Parade Convertibles, Minsk, Belarus, June 2017.

Independence Day in Belarus is celebrated annually on 3 June and there is always a significant military component.  Other than the PRC, Belarus is the only known operator of the Honqqi and the four-door convertible parade cars were apparently a "gift" (as opposed to foreign aid) from the Chinese government but the aspect of this photograph which attracted some comment was whether the hats worn by generals in Belarus were bigger than the famously imposing headwear of the army of the DPRK (Democratic People’s Republic of Korea (North Korea)); analysts of military millinery appeared to conclude the dimensions were similar.  Purists traditionally describe this style of coach-work as "four-door cabriolet" and it was "Cabriolet D" in the Daimler-Benz system but the "parade convertible" is a distinct breed and often includes features such as grab bars for those standing, microphones and loud-speakers so the “enthusiastic and happy” crowd miss not one word.   

Hongqi L5 state limousine.

The car carrying President Xi was the Hongqi L5, the state limousine of the PRC, the coachwork styling a deliberately retro homage to the Hongqi CA770, the last in the line (dating from 1958) of large cars built almost exclusively for use by the upper echelons of the CCP.  Most of the earlier cars were built on the large platforms US manufacturers used in the 1960s and were powered by a variety of US-sourced V8 engines but the L5 was wholly an indigenous product, built with both a 6.0 litre (365 cubic inch) V12 and 4.0 litre (245 cubic inch) V8 although neither configuration is intended for high-performance.  Interestingly, although Hongqi L5 have produced a version of the L5 with four-door convertible coachwork as a formal parade car and they have been used both in the PRC and in Belarus, the general secretary conducted his review in a closed vehicle with a sunroof.

US President Richard Nixon (1913-1994, US president 1969-1974) with Anwar Sadat (1918–1981; President of Egypt 1970-1981) in a 1967 Cadillac convertible, Alexandria, Egypt, June 1974.  On that day, the motorcade was 180-strong and unlike the reception his appearance in the US now induced, the Egyptian crowd really did seem genuinely enthusiastic and happy.  Within two months, in disgrace because of his part in the Watergate Affair, Nixon would resign.

The CCP didn’t comment on the choice of a car with a sunroof and it may have been made on technical grounds, the provision of a microphone array presumably easier with the roof available as a mounting point and given the motorcade travelled a higher speed than a traditional parade, it would also have provided a more stable platform for the general secretary.  It’s not thought there was any concern about security, Xi Jinping (for a variety of reasons) safer in his capital than many leaders although heads of state and government became notably more reticent about travelling in open-topped vehicles after John Kennedy (1917–1963; US president 1961-1963) was assassinated in 1963.  Some, perhaps encouraged by Richard Nixon being greeted by cheering crowds in 1974 when driven through the streets of Alexandria (a potent reminder of how things have changed) in a Cadillac convertible, persisted but after the attempt on the life of John Paul II (1920–2005; pope 1978-2005) in 1981, there’s been a trend to roofs all the way, sometimes molded in translucent materials of increasing chemical complexity to afford some protection from assassins.

Military parade marking the 70th anniversary of the founding of the PRC, Beijing, China, 1 October 2019.  Great set-piece military parades like those conducted by the PRC and DPRK (recalling the spectacles staged by both Nazi Germany (1933-1945) and the Soviet Union (1922-1991) are now packaged for television and distribution on streaming platforms and it may be Donald Trump (b 1946; US president 2017-2021 and since 2025) was hoping the "Grand Military Parade" he scheduled in 2025 for his 79th birthday (ostensibly to celebrate 250 years since the formation of the US Army) would display the same impressive precision in chorography.     

Covering all possibilities during the 24 hour cycle.  US advertisement (1974) for the Renault 17 Gordini Coupe Convertible, the Gordini tag adopted as a "re-brand" of the top-of-the-range R17 (1971-1979).  Gordini was a French sports car producer and tuning house, absorbed by Renault in 1968, the name from time-to-time used for high-performance variants of various Renault models.

Renault over the decades made the occasional foray into the tempting US market but all ended badly in one way or another, their products, whatever their sometimes real virtues, tending not to be suited to US driving habits and conditions.  Sunroofs had long been popular in Europe and, noting (1) what was assumed to be the demise of the convertible and (2) Lincoln's coining of "moon roof", Renault decided Americans deserved a sunroof, moonroof & starroof, all in one.  Actually, they got even more because there was also a removable, fibreglass hardtop for the winter months, Renault correctly concluding there would be little demand for a rainroof.  Physically large as it had to be, unlike a targa top, the 17's panel was intended (like other hardtops) to be stored in a garage until the warmer months.  One quirk of the R17's nomenclature was in Italy, in deference to the national heptadecaphobia, the car was sold as the R177 but the Italians showed little more interest than the Americans.

Porsche, sunroofs, weight distribution and centres of gravity 

Porsche 917K, Le Mans, 1970.

Porsche in the early 1970s enjoyed great success in sports car racing with their extraordinary 917 but greatly innovation and speed disturb the clipboard-carriers at the Fédération Internationale de l'Automobile (the FIA; the International Automobile Federation) which is international sport's dopiest regulatory body.  Inclined instinctively to ban anything interesting, the FIA outlawed the 917 in sports car racing so Porsche turned its glance to the Can-Am (Canadian-American Challenge Cup) for unlimited displacement (Group 7) sports cars, then dominated by the McLarens powered by big-displacement Chevrolet V8s.  Unable to enlarge the 917's Flat-12 to match the power of the V8s and finding their prototype Flat-16 too bulky, Porsche resorted to forced aspiration and created what came to be known as the "TurboPanzer", a 917 which in qualifying trim took to the tracks with some 1,500 horsepower (HP).  There's since been nothing quite like it and for two years it dominated the Can-Am until the first oil shock in 1973 put an end to the fun.  However, the lessons learned about turbocharging the factory would soon put to good use.

The widow-maker: 1979 Porsche 930 Turbo (RoW (rest of the world (ie Non-NA (North American) market) model) in the “so 1980s” Guards Red with “Sunroof Delete” option.

Although an RoW car, this one has been "federalized" for registration in the US including the then required sealed-beam headlights, fitted inside the "sugar-scoop" housings.  Curiously, although the term “sunroof delete option” is often applied to the relative few 930s with solid metal roofs, there was at the time no such 930 option code and, the sunroof being listed as “standard equipment” on 930s, if a customer requested one not be fitted, what the factory did was not include option 9474 (electric sunroof) on the build sheet.  Later the companion option codes 650 (Sunroof) and 652 (Delete Sunroof) became part of the list for all models.  Rare though it may be in some Porsches, for some the “sunroof delete” thing is surprisingly desirable and in the aftermarket, it's possible to purchase “sunroof delete” panels which convert a sunroof-equipped car into one with a solid metal roof.  They are bought usually by those converting road-going cars for track use, the removal of the 29 lb-odd (13 kg) assembly not only saving weight but also lowering the centre of gravity.

1977 Porsche 930 “Sunroof Coupé” in Talbot Yellow.

Introduced in 1975, the 911 Turbo (930 the internal designation) had been intended purely as a homologation exercise (al la the earlier 911 RS Carrera) so the engine could be used in competition but so popular did it prove it was added to the list as a regular production model and one has been a permanent part of the catalogue almost continuously since.  The additional power and its sometimes sudden arrival meant the early versions were famously twitchy at the limit (and such was the power those limits were easily reached if not long explored), gaining the machine the nickname “widow-maker”.  There was plenty of advice available for drivers, the most useful probably the instruction not to use the same technique when cornering as one might in a front-engined car and a caution that even if one had had a Volkswagen Beetle while a student, that experience might not be enough to prepare one for a Porsche Turbo.  When stresses are extreme, the physics mean the location of small amounts of weight become subject to a multiplier-effect and the advice was those wishing to explore a 930's limits of adhesion should get one with the rare “sunroof delete” option, the lack of the additional weight up there slightly lowering the centre of gravity.  However, even that precaution may only have delayed the inevitable and possibly made the consequences worse, one travelling a little faster before the tail-heavy beast misbehaved.

Porsche 911 Carrera S, Pacific Coast Highway in Santa Monica, Los Angeles, June 2012.

Although it seems improbable, when in 2012 Lindsay Lohan crashed a sunroof-equipped Porsche 911 Carrera, it's not impossible the unfortunate event may have been related to the slight change in the car's centre of gravity when fitted with a sunroof.  She anyway had some bad luck when driving black German cars but clearly Ms Lohan should avoid Porsches with sunroofs.

The interaction of the weight of a 911’s roof (and thus the centre of gravity) and the rearward bias of the weight distribution was not a thing of urban myth or computer simulations.  In the February 1972 edition of the US magazine Car and Driver (C&D), a comparison test was run of the three flavours of the revised 911 (911T, 911E & 911S), using one of each of the available bodies: coupé, targa & sunroof coupé, the latter with the most additional weight in the roof.  What the testers noted in the targa & sunroof-equipped 911s was a greater tendency to twitchiness in corners, something no doubt exacerbated in the sunroof coupé because the sliding panel’s electric motor was installed in the engine bay.  C&D’s conclusion was: “If handling is your goal, it's best to stick with the plain coupe.”  

The Porsche 911 E series and the Ölklappe affair

1971 Porsche 911S (note the flap for the oil filler cap behind the passenger-side door (US market model and thus left-hand drive (LHD)).  The factory confirmed this car was built in July 1971, despite many references to E series production beginning in August.

Although in C&D's 1972 comparison test there was much focus on the rearward weight bias, the three 911s supplied actually had a slightly less tail-heavy weight distribution than either that season's predecessor or successor.  Porsche in 1971 began the build of its E series update (produced between July 1971-July 1972 and generally known as the “1972 models”) of the then almost decade-old 911 and in addition to the increase in the flat-six’s displacement from 2.2 litres (134 cubic inch) to 2.3 (143) (although always referred to as the “2.4”), there were a myriad of changes, some in response to US safety & emissions legislation while others were part of normal product development.  One of latter was the placing of the hinged-flap over the oil filler cap behind the right side door, something necessitated by the dry sump oil tank having been re-located from behind the right rear wheel to in front, one of a number of design changes undertaken to shift the weight distribution forward and improve the handling of the rear-engined machine’s inherently tail-heavy configuration.  In Germany, the addition was known variously as Ölklappe, Oil Klapper or Vierte Tür (fourth door, the fuel filler flap being the third).  Weight reduction (then becoming difficult in the increasingly strict regulatory environment), especially at the rear, was also a design imperative and the early-build E series cars were fitted with an aluminum engine lid and license-plate panel although these components were soon switched to steel because of production difficulties and durability concerns.

Where the troubles began:  The fuel filler flap on the left-front fender (left) and the oil filler flap on the right-rear fender (right).  Apparently, not even the “◀ Oil” sticker in red was sufficient warning.

For the E series 911s, Porsche recommended the use of a multigrade mineral oil (SAE 20W-50 or SAE 15W-40, depending on climate) but were aware those using their vehicles in competition sometimes used a high-viscosity SAE 50 monograde.  With the car’s 10 litre (10.6 US quarts, 8.8 Imperial quarts) oil tank, the fluid’s weight would be between 8.5-9.1 kg (18.7-20.0 lb) and the physics of motion meant that the more rearward the placement of that mass, the greater the effect on the 911’s handling characteristics.  It was thus a useful contribution to what would prove a decades-long quest to tame the behaviour of what, in the early versions, was a car regarded (not wholly unfairly) as handling like “a very fast Volkswagen Beetle” and ultimately the engineers succeeded, it being only at the speeds which should be restricted to race tracks the 911s of the 2020s sometimes reveal the implications of being rear-engined.

VDO instruments in 1971 Porsche 911S.  In home market cars, the oil pressure gauge (to the left of the centrally mounted tachometer) was labelled DRUCK.

However, when in August 1972 the revised F series entered production, the oil tank was back behind the rear wheel and the filler under the engine lid, the retrogressive move taken because there had been instances of gas (petrol) station attendants (they really used to exist) assuming the oil filler flap was the access point for the gas cap and, to be fair, it was in a location used for gas on many front-engined cars (a majority of the passenger-car fleet in most markets where Porsche had a presence).  Quite how often this happened isn’t known but it must have been frequent enough for the story to become part of the 911 legend and the consequences could have been severe and rectification expensive.  The factory paid much attention to oil and also ensured drivers could monitor the status of the critical fluid; all air-cooled 911s ran hot and the more highly tuned the model (in 1971-1972 the 911T, E & S in increasing potency), the hotter they got.  As well as being a lubricant, engine oil functions also as a coolant and the VDO instrumentation included gauges for oil level, oil temperature, and oil pressure; for all three to appear in a road car was unusual but being air-cooled and thus with no conventional fluid coolant, the oil's dynamics were most important.

Friday, February 28, 2025

Corvette

Corvette (pronounced kawr-vet)

(1) In historic admiralty use, a flush-decked warship of the seventeenth & eighteenth centuries having a single tier of guns and one size down from a frigate; in the US Navy called a sloop of war (usually truncated to sloop).

(2) In current Admiralty use, a lightly armed and armored blue-water warship, one size down from a frigate and capable of transoceanic duty.

(3) A GRP-bodied sports car produced in the US since 1953 by General Motors’ (GM) Chevrolet division.

1630–1640: From the French, from the Middle French corvette (a small, fast frigate), from the Middle Dutch corferkorver, corver (pursuit boat), the construct on the model of corf (fishing boat (literally “basket”)) + -ette (the diminutive suffix) or the Middle Low German korf (small boat; literally “basket”).  The source of both was the Latin corbis (basket) and, despite there existing also in Latin the corbita (navis) (slow-sailing ship of burden, grain ship), again from corbis, the relationship between this word and the later European forms is disputed.  The suffix –ette was from the Middle English -ette, a borrowing from the Old French -ette, from the Latin -itta, the feminine form of -ittus.  It was used to form nouns meaning a smaller form of something.  The Italian corvette & the Spanish corbeta are French loan-words, the German equivalent being korvette.  The obsolete alternative spelling was corvet.

Naval Battle between the French corvette La Bayonnaise and the British frigate HMS L'Embuscade, 14 December 1798, by Jean Francois Hue (1751-1823).

Historically, the term corvette, as applied to warships by various navies, can be misleading, the vessels varying greatly in size, displacement, armament and suitability, making some mor suitable than others for use on the high seas (ie the so-called "blue water").  As a general principle, a corvette was understood to be a warship larger than a sloop, smaller than a frigate and with fewer and sometimes smaller-bore guns than the latter, always arrayed on a single deck.  Although envisaged originally as a blue-water ship, they were allocated mostly to costal duties (ie "white water") or the range of activities smaller vessels fulfilled in a fleet support role.  In the manner of military mission creep, overlap emerged and in some navies there were occasions when newer corvettes were at least as large and well-gunned as some frigates although the Royal Navy tended to maintain the distinctions, finding the smaller ships a useful addition in the seventeenth century, their fast build rate affording the Admiralty the means quickly to augment the reach and firepower of a fleet.  To the British Admiralty, they anyway were still called sloops and it wasn’t until the 1830s the first vessels designated corvettes left UK shipyards.  It seems to have been the French Navy which first described the “big sloops” as corvettes but, whether by strategic design or in an attempt to confound the espionage activities of opponents, by the late eighteenth century, French naval architects designing corvettes the British would have defined as frigates.

HMCS Bowmanville (K 493), Royal Canadian Navy Corvette of WWII.

Because of the nature of sea battles prior to World War II (1939-1945), ships the size of the corvette tended to be neglected, the interest in smaller warships centred on the ever smaller torpedo boats and the two work-horses of the fleets, the frigate and destroyer, both of which were better suited to support cruisers patrolling the trade routes of the empire and the battleships of the high-seas fleets.  What saw a revival of interest was the war-time need to protect the trans-Atlantic and Arctic Sea convoys.  While the small corvettes, marginal in blue-water conditions, weren’t ideal for the role, they could be produced quickly and cheaply and, as a war-time necessity, were pressed into service as a stop-gap until more destroyers became available.  An additional factor was their small size which meant they could be built in many of the small, civilian shipyards which would have lacked the capacity to construct a frigate, let alone a destroyer.  Since the war, corvette has as a designation essentially become extinct but in many navies there have long been in service frigates and fast patrol boats which correspond in size with the traditional WWII corvette.


The early Chevrolet Corvettes, C1, C2 & C3 

1953 Corvette.

By 1952, the success in the US of MG and Jaguar had made it clear to Chevrolet that demand existed for sports cars and the market spread across a wide price band so with the then novel GRP (glass reinforced plastic, soon better known in the US as "fiberglass") offering the possibility of producing relatively low volumes of cars with complex curves without the need for expensive tooling or a workforce of craftsmen to shape them, a prototype was prepared for display at General Motors’ 1953 Motorama show.  Despite the perception among some it was the positive response of the Motorama audience which convinced GM’s management to approve production, the project had already be signed-off but the enthusiastic reaction certainly encouraged Chevrolet to bring the Corvette to market as soon as possible.  The name Corvette was chosen in the hope of establishing a connection with the light, nimble naval vessels and indisputably the modern lines made the essentially pre-war MGs look as archaic as they were and even the Jaguar XK120 was now obviously an evolution of the way sports cars might have looked by 1945 had the war not postponed progress.

1953 Corvette.

That haste however brought its own, unique challenges.  In 1953, Chevrolet had no experience of large-scale production of GRP-bodied cars but neither did anybody else, GM really was being innovative.  The decision was therefore taken to build a batch of three-hundred identical copies, the rationale being the workers would be able to perfect the assembly techniques involved in bolting and gluing together the forty-six GRP pieces molded by an outside contractor.  Thus, by a process of trial and error, were assembled three hundred white Corvettes with red interiors, a modest beginning but the sales performance was less impressive still, fewer than two-hundred finding buyers, mainly because the rate of production was erratic and with so few cars available for the whole country, dealers weren’t encouraged to take orders; uncertainty surrounded the programme for the whole year.  Seldom has GM made so little attempt actually to sell a car, preferring to use the available stock for travelling display purposes, tantalizing those who wanted one so they would be ready to spend when mass-production started.

1954 Corvette.

The first Corvettes had been produced on a small assembly line in Flint, Michigan to allow processes closely to be observed & optimized but by late 1953, Chevrolet was ready for high-volume runs, moving production to a plant in Saint Louis, Missouri with the capacity to make ten-thousand a year.  In anticipation of the Corvette being a regular-production model, three additional colors (black, red, and blue) were offered and the black soft-top was replaced by one finished in tan.  However, despite the enhancements, demand proved sluggish and fewer than four-thousand were sold in 1954 and there were reasons.  In 1961, Jaguar would stun the world with its new sports car, powered by a triple-carburetor 3.8 litre straight-six but in 1953, although Chevrolet’s Corvette boasted the same specification and a much admired body, it wasn’t anything like the sensation the E-type would be at Geneva.  The 1954 Corvette had gained a revised camshaft which increased power by 5 horsepower (hp), an output respectable by the standards of the time but the only transmission available was the Powerglide, a two speed automatic which for robustness and reliability matched the Blue Flame six-cylinder engine (an updated version of the pre-war "Stovebolt") to which it was attached but neither exhibited the dynamic qualities which had come to be expected from a sports car although owners would have to get used to it: the Powerglide would be the only automatic transmission offered in a Corvette until 1968.  In truth, the Corvette was betwixt & between; not quite a sports car yet lacking the creature comforts to appeal to those wanting a relaxed GT (grand-tourer).

1955 Corvette V8.

Chevrolet in 1955 solved the problem of the Corvette’s performance deficit by slotting in the new 265 cubic inch (4.3-litre) V-8 which would later come to be called the small-block and become a corporate stable, appearing over the decades by the million in various forms in just about every Chevrolet and some models from other divisions (though this corporate sharing would not be without controversy).  Rated now at 195 hp which felt more convincing than the previous year’s 155, it was offered also with a three-speed manual transmission and could now run with the Jaguars, Mercedes-Benz and Ferraris on both road and track; the Corvette had become a sports car and while not cheap, compared with the competition, it was conspicuously good value.  Most 1955 Corvette V8s were fitted with the two-speed Powerglide automatic transmission but the factory's records confirm there were 19 with the three-speed manual (as "special orders", the manual unlisted as an option in most of sales literature).

1956 Corvette.

The V8 option had been introduced late in 1955 but the response of buyers had convinced Chevrolet where the future lay; once available, only seven had chosen the old Blue Flame six so for 1956 the Corvette became exclusively V8-powered, a specification by 2025 still not deviated from (although auxiliary electric motors would in the next century appear).  To emphasize the dual role the car now plausibly could fulfil, the Powerglide became optional and revisions to the engine meant power was up to 210 hp although for those who wanted more, a dual four-barrel carburetor setup could be specified which raised that to 225.  Still made from GRP, the revised styling hinted at some influence from the Mercedes-Benz 300SL (W198, 1954-1963) but had practical improvements as well, external door handles appearing and conventional side windows replaced the fiddly removable curtains, a civilizing addition some British roadsters wouldn’t acquire until well into the next decade.  There was also the indication Chevrolet did take seriously the dual role for in addition to the Powerglide remaining available, buyers could now specify a power-operated soft top and internal company documents noted the appeal of this feature "to women", a target market even then.  Whether it was sports car or GT was now up to the customer.

Jaguar E-Type advertising copy, 1971.

Chevrolet's experience in finding the six-cylinder Corvette had limited appeal once their V8 became available was in 1971 reprised across the Atlantic when Jaguar released the Series 3 E-Type (sometimes known in the US as XKE).  Jaguar's V12 project had a long gestation and by the time eventually it entered production, the 420G (1961-1970 and known originally as the Mark X) which had been intended as its first recipient, had been retired.  The task of engineering the much smaller XJ (introduced in 1968) to house the V12 was absorbing much energy so it was the E-Type in which the new engine was first used.  Jaguar made the effort to prepare the new S3 E-Type to use both the long-running, 4.2 litre (258 cubic inch) XK straight-six and the 5.3 litre (326 cubic inch) V12, including printing promotional material, even glossy, full-color, multi-lingual brochures.

Jaguar E-Type advertising copy, 1971.

However, before series production began, the decision was taken to offer the S3 only with the V12 and although there are tales of six XK-engined prototypes having been built, the Jaguar-Daimler Historic Trust insists the true number was four (2 roadsters & 2 coupés with one right hand drive (RHD) and one left hand drive (LHD) version of each); the LHD coupé with a manual transmission survived although when offered at auction in England, its rarity (genuinely it is unique) didn't attract a premium as it sold for a price little different from what might be expected for a V12 in the same condition.  By 1974, when the effects of the spike in the price of oil began to affect demand for engines as thirsty as the V12, the E-Type was in its last days so the company made no attempt to resurrect one with the smaller engine, unlike Mercedes-Benz which quickly made available in the R107 roadster and C107 coupé the 2.7 litre (168 cubic inch) six as an alternative to the 3.5 (214 cubic inch) & 4.5 (276 cubic inch) V8s.  Although it couldn't at the time have been predicted, the R107 in both six & eight cylinder form remained available until 1989 so the efforts taken during the first oil shock proved worthwhile.  It wouldn't be until 1983 Jaguar offered the XJS (1975-1996 and (sort of) the E-Type's replacement) with a six-cylinder engine and, remarkably, the XJS would enjoy a longer life even than the R107, the last not leaving the factory until 1996.           

1957 Corvette (fuel injected).

In 1957, things started to get really serious, a four-speed manual transmission was added, the V8 was bored out to 283 cubic inches (4.6 liters) which increased power and, in an exotic touch which matched the Mercedes-Benz 300 SL, Rochester mechanical fuel-injection was an (expensive) option, allowing the Corvette to boast an engine with one hp per cubic inch, something in the past achieved only by the big dual-quad Chrysler Hemis, offered only in heavyweightmachines which, although fast, were no sports cars, heavy cruisers rather than corvettes.  Unlike the electronic fuel-injection systems others flirted with in the era, Rochester's mechanical system proved reliable although it did demand well-trained mechanics to ensure it remained in tune.

1958 Corvette.

A noted change for 1958 was the tachometer moving from the centre of the dashboard to a place directly in from to the driver, probably a wise move given the propensity of the fuel-injected engine to high-speed and output continued to rise, by 1960 315 hp would be generated by the top option.  One big styling trend in 1957 had been the quad headlamps allowed states relaxed their lighting regulations and these were added, unhappily according to some, to the Corvette for 1958.  However, even many of those of those who admired the four-eyed look thought the lashings of chrome a bit much.  Chrome was quite a thing in Detroit by 1958 and De Sotos, Lincolns, Buicks and such were displaying their shiny splendour but it probably didn’t suit the Corvette quite so well which was unfortunate given it was adorned with much, even the headlight bezels getting a coating.  A change of management at the top of Chevrolet's styling department ensured 1958 was peak-chrome for the sports car; cars from other divisions would for some time continue to drip the stuff but the Corvette would be notably more restrained.

1962 Corvette.

Although the changes since 1963 had been many, the Corvette was still in its first generation but the 1962 model would be the end of the line.  The front end had earlier been revised from its chromed origin and in 1961 a redesigned rear arrived which saw the debut of the quad-taillight design which would for decades remain a distinctive feature.  1962 saw the introduction of a 327 cubic-inch (5.3 litre) V8, the fuel-injected version now up to 360 hp.  The C2 would be the last to include a trunk (boot) lid until the release for the C5 for the 1998 season, access to the storage area in the "lidless" era being a reach behind the seats.  Rear-deck mounted luggage racks became a popular option and one which to this day remains polarizing.

1963 Corvette Coupe. This was one of GM's official publicity stills and one can see why the decision was taken not to include a trunk lid but the absence enhanced structural integrity and it was this Chevrolet chose to emphasize.

For 1963, unusually, the big news wasn’t what was under the hood (bonnet).  The 327 V8 was carried over from 1962 but, other than the drive-train, it was a new car (later referred to as the C2, the 1953-1962 models now retrospectively dubbed the C1), offered for the first time as a coupé as well as the traditional convertible and with a revised frame which included independent rear suspension, a rarity at the time on US-built vehicles.  Chevrolet officially had no involvement in racing but understood the Corvette’s appeal to those who did and in 1963 offered Regular Production Option (RPO) Z06 which included an improved brake and suspension package.  Available only in conjunction with the 360 hp engine and a four-speed manual transmission, around two-hundred were built, most of them coupés.

One quirk of the 1963 coupés was the "split-window" design of the rear glass.  After the release, it became a source of debate within Chevrolet and eventually, the "anti-split" prevailed, a single piece of glass substituted in 1964 which of course rendered the 1963 cars instantly dated.  As a result, a small-scale industry sprung up offering owners the chance to update their look, they be seen driving "last year's model" and that wasn't exclusively a '63 Corvette thing, the idea even having enjoyed corporate support.  When the 1936 Ford V8 was introduced, so effective was the restyling that despite behind the cowl it being essentially identical to the 1935 model, the effect was something was which looked "all new".  That was thought to create a marketing opportunity and in a novel exercise, the factory offered dealers a a kit containing all the front-clip sheet metal needed to make a '35 look like a '36.  The marketing textbooks probably would suggest that was a bad idea because presumably it would reduce sales of new Fords but economic realities anyway made it a one-off venture: at US$213.28 plus a US$69.00 labor charge, the kit seemed compelling to few when a brand new 1936 Ford V8 could be bought for as little as US$510.00.  Years after the "fake" 1964 Corvettes were created, the uniqueness of the split-window cars made them a a much prized collectable and another small-scale industry briefly flourished converting modified ones back and, whether true or urban myth, it’s said as many as 2% of the split-window coupés which now exist may be later models with a bit of judicious back-dating.

1963 Chevrolet Corvette Grand Sports, Nassau Speed Week, December 1963.  The additional apertures on the rear facia were not for taillights but air-extraction ports to prevent the panel acting like a "parachute" which not only reduced speed but also induced lift, creating instability.

One aborted C2 project was the Grand Sport (GS) Corvette, a competition oriented model using an all-aluminum 377 cubic inch (6.2 litre) version of the small-block V-8 (making a reputed 550 hp) and a structure which had been subjected to an extensive weight-reduction programme.  It had been intended to build a run of 125 (some sources say 100 in competition trim with a further 25 as "road" versions with creature comforts) in order to homologate it in certain racing categories but GM, still (unlike its competitors) taking seriously the need to make it appear it was maintaining the industry's agreed ban on participation in motorsport, cancelled the programme after five (three coupés and two roadsters) had been built; all survived and are now multi-million dollar collectibles, something which has inspired the creation of a number of clones.  One quirk of the GS was the coupés were fitted with a one-piece rear window and so the three are the only 1963 Corvettes to leave the factory without the famous split-screen (which really was two separate pieces of glass).  The very presence of the split screen was the subject of a well-documented squabble within Chevrolet and ultimately, the design team prevailed with a single piece of glass appearing for the 1964 coupés. 

1965 Corvette 396 Convertible with hard-top, side exhaust pipes and Kelsey-Hayes cast aluminum wheels (still with knock-off hubs that year).

Although the Corvette had gained powerful, fuel-injected engines and an effective independent rear suspension, the drum brakes remained the package’s weak link.  In 1964 option J65 (US$53.80) bundled the power assistance (as stand-alone option J50 retailing at US$43.05) with sintered metallic linings for the brakes but while this improved the retardation and especially the propensity for performance to fade in sustained use, the combo couldn’t match what could be achieved with disk brakes.  Still, the motoring press commended option and it persuaded 4,780 buyers to tick the box.  At a hefty US$629.50 however then was option J56, described as “Special Sintered Metallic Brake Package” and that it was available only with a fuel-injected engine, a four-speed transmission and a Positraction rear end was an indication it was intended only for those who operated in “extreme conditions” (ie on race tracks).  Effective they certainly were but, noisy and with high pedal pressures, they were not suitable for street use and a scant 29 customers were tempted.  In what was an overdue upgrade, Chevrolet made four-wheel disc brakes standard for the 1965 model year although the drums remained available (as delete-option code J61) for anyone who wished to save a few dollars.  Those who opted to eschew the dramatic improvement in braking offered were probably specialists; because of internal friction the discs did impose a (very slight) performance and economy reduction which was why drums were long preferred on the NASCAR ovals where brakes are rarely applied and fractions of a second per lap can be the difference between winning and losing,  Only 316 Corvette buyers chose to save the US$64.50 and the disks definitely were a good idea if the newest engine was chosen.  Although developed by  Kelsey-Hayes, the brakes were manufactured for Chevrolet by Delco Moraine and included a pair of small drum brakes in the rear hubs to provide a parking brake, something difficult to engineer with disks.  Kelsey-Hayes also produced the optional aluminium wheels but at US$322.80 the take-up rate was low and many C2 Corvettes now are fitted with modern reproductions of the originals; the same applies to the side exhaust-pipes (a new option for 1965 at US$134.50), many more Corvettes now so equipped than the 759 which in 1965 left the factory. 

The distinctive "bent needles" were last used on the Corvette's instruments in 1964.

As a mid-year release in 1965, the big-block 396 cubic-inch (6.5 litre) V-8 became available and it was rated at 425 hp, a figure few doubted after seeing the performance figures.  Predictably, given the fuel-injected 327 was rated at 375 hp but cost US$538.00 against US$292.70 for the more muscular big-block, only 771 chose the former while 2157 opted for the 396 which must have seemed a bargain compared to the US$202.30 Chevrolet charged for the 36 (US) gallon (136 litre) fuel tank (available only for the coupé).  This cost-breakdown must be considered in the context of the Corvette's base price (US$4106.00 for the convertible and US$1321.00 for the coupé) and the air-conditioning ordered by only 2423 buyers (9.7%); at US$421.00 it increased the invoice by some 10%).  There were charms only the fuel-injected unit deliver but the customer is always right and before the year was out, the Rochester option was retired and it wouldn’t be until 1982, in the age of the micro-chip, that Chevrolet would again offer a fuel-injected Corvette.  Buyers clearly were convinced by the big-block idea but the sections of the motoring press were ambivalent, Car & Driver's (C&D) review suggesting that while "...there are many sports cars which really need more power, the Corvette isn’t one of them."  Unlike the chauvinistic English motoring press which tended to be a bit one-eyed about things like Jaguars and Aston-Martins, there were many in the US motoring media who really didn’t approve of American cars and wished they were more like Lancias.  People should be careful what they wish for.

1967 Corvette L88 convertible with side exhaust pipes and Kelsey-Hayes cast aluminum wheels (with five-stud hubs that year).

Maybe even Chevrolet had moments of doubt after reading their copy of C&D and thought the 396 Corvette might have been a bit much because after providing cars for the press to test, they issued a statement saying the 396 wouldn’t be available in the Corvette after all but would be offered in the intermediate Chevelle as well as the full-sized cars.  The moment however quickly passed, the 396 Corvette remaining on the books and by 1966 Chevrolet certainly agreed there was no substitute for cubic inches, the 396 replaced by a 427 cubic-inch (7.0 litre) iteration of the big-block.  For 1966 it was still rated at 425 hp but in 1967, a triple carburetor option sat atop the top engine, gaining an additional ten hp.  There was however another, barely advertised and rarely discussed because of its unsuitability for street use and this was the L88, conservatively rated at 430 hp but actually developing between 540-560.  Essentially a road-going version of the 427 used in the (unlimited displacement FIA Group 7 sports-car) Can-Am race series, just 20 were sold in 1967, the survivors among the most sought-after Corvettes, one selling at auction in 2014 for US$3.85 million.

By the 1960s it was common for hard-tops to be on the option list of a roadster (in the era there was even one company which briefly (and unsuccessfully) offered GRP versions for Detroit's full-size convertibles) but Chevrolet gave C2 Corvette buyers the choice to have both a hard-top & soft-top or just one of the two.  Remarkably (and presumably in places where rain events were predictable), a number of buyers did take the hard-top only course and the configuration wasn't unique to Chevrolet, Mercedes-Benz in some years offering its "Pagoda" roadster (W113; 1963-1971) with only a hard-top although it was listed a separate model: the "California Coupé" which, despite the name, was still a convertible and one which offered the additional practicality of a folding bench seat in the rear compartment, permitting (cramped) seating for two.   

Joe Biden (b 1942; US president 2021-2025) in his 1967 Corvette Convertible.

Given he was already 62 when Mean Girls was released in 2004, most assumed it must have been an intern who provided the intelligence (1) that October 3 is "Mean Girls Day" and (2) "Get in loser, we're going shopping" is a line waiting to be a meme.  Thus the tweet in 2022 although there was some subterfuge involved, the photograph actually from a session at his Wilmington, Delaware estate on July 16 2020.  The excuse for not taking a new snap probably was legitimate, the Secret Service most reluctant to let him behind the wheel (and they probably had many reasons to be worried).  The presidency is often called the most powerful office in the world but he's still not allowed to drive his own Corvette (all ex-presidents actually forbidden again to take the wheel on public roads) and George HW Bush (George XLI, 1924-2018; US president 1989-1993) encountered push-back when he refused to eat broccoli, apparently still scarred by the experience when young of having the green stuff forced on him by his mother.  He was far from the only head of state or government to have had unresolved issues with his mother.

President Biden's Corvette Sting Ray (it was two words in the C2 era) was ordered with the base version of the 327 rated at 300 hp, coupled to a four-speed manual gearbox.  For what most people did most of the time the combination of the base engine and the four-speed was ideal for street use although there were some who claimed the standard three-speed transmission was even more suited to the urban environment, the torque-spread of even the mildest of the V8s such that the driving experience didn't suffer and fewer gearchanges were required.  Those wanting the automatic option were restricted still to the old two-speed Powerguide, the newer Turbo-Hydramatic with an extra ratio simply too bulky to fit (some subsequently have modified their early cars with a Turbo-Hydramatic but they didn't have to organize the production line upon which thousands would be built).  The 1967 cars were actually an accident of history, the C3 (slated for release as a 1967 model) delayed (the issues said to be with with aerodynamics which in the those days meant spending time in the wind tunnel and on the test track, computer modelling of such things decades away) by one season.  Sales were thus down from 1966 as the new, swoopy body was much anticipated but the 1967 cars are now among the most coveted.

1967 Corvette 427-400 Tri-Power Convertible with Powerglide.

The original 1953 Corvette had used the two-speed Powerglide automatic transmission because Chevrolet at the time didn’t have available a suitable manual gearbox.  The company was however innovative in the implementation, the floor-shift mechanism being the first known instance of the location for an automatic’s lever and it protruded from the side of the housing, something which doubtless seemed exotic but was really a short-cut by the engineers because it meant they could use the existing take-up for the linkage (Chrysler as late as 1963 used the same arrangement 300J).  The configuration really didn’t detract much from the driving experience because the Powerglide was, by the standards of the era, quick-shifting (though with only two ratios such events were anyway rare) and efficient which, combined with the light weight of the GRP body, made the thing a match in performance for many, heavier, V8-powered cars.  Even after manual gearboxes were added to the option list (a three-speed in 1955 and a four-speed two year later), the Powerglide remained available although in a typical year it was chosen by some 10% of buyers and as more powerful engines appeared (some with dual four-barrel carburetors, some with fuel-injection), these were offered only with the manual gearbox and the preference of the buyers who preferred the automatic was always slanted to the least powerful.

1967 Corvette 427-390 Coupe with Powerglide and air-conditioning.

When the big-block 396 debuted in the Corvette in mid 1965, it was available only with the four-speed manual, a limitation continued when it was replaced for the next season by the 427.  Unexpectedly however, the Powerglide in 1967 appeared on the option list for both the 390 (four barrel) and 400 (3 x 2 barrel) horsepower iterations although the more powerful (which used solid valve lifters and had higher redlines), retained the manual-only restriction.  Demand for the big-block / Powerglide combination was subdued: of the 2324 1967 Corvettes ordered with the automatic gearbox, 1725 used the 300 HP 327 and only 599 the 427, 392 with the 390 HP version, 207 with the 400.  In an indication of Chevrolet’s expectations of the Corvette buyer profile attracted to the Powerglide, air-conditioning was available with both the 390 & 400 HP engines.  It was the last year the Powerglide would appear in the Corvette, the platform of the succeeding C3 designed to accommodate the physically larger Turbo-Hydramatic.  A more modern and much superior design, the availability of the new three-speed transmission was welcomed but the old two-speed did have the charm of being able to hit 90 mph (145 km/h) in first gear, something of genuine benefit to the drag racing crowd who to this day continue to prize the Powerglide for (1) its robustness and (2) the ability to complete a quarter-mile (402 m) run with only one gear change, slicing priceless fractions of a second from the ET (elapsed time).  One trend which began with the debut of the new transmission in the Corvette was the take-up rate in the sports car essentially doubled; in 1969 the Turbo-Hydramatic was chosen by some 20% of buyers and the not only would tat continue to rise by 1982 (its last year of production), the Corvette was automatic only and by then the lower power and torque ratings meant the Turbo-Hydramatic had been replaced by a unit which was more efficient (although, as some would discover, it was also less robust).  When the mid-engined C8 Corvette was released in 2020, there was no conventional manual gearbox available, that decision taken for the same reason Ferrari had discontinued use almost a decade earlier: the automatic out-performed the manual in every aspect.  Curiously, among the Ferrari crowd, the famous open-gate shifters never lost the appeal and the factory must have noted both the emergence of a small industry converting modern Ferraris to use a fully manual transmission and buyer feedback because in 2025 it was reported there may soon again be a Ferrari with a clutch pedal and gated shifter.    

Same L72 engine, different stickers: An very early one (left) with a "450 HP" sticker and a later build (right) with a "425 HP".  

Most fetishized by the Corvette collector community are (1) rare models, (2) rare options singularly or in combinations and (3) production line quirks, especially if accompanied by documents confirming it was done by the factory.  There were a few of all of these during the Corvette’s first two decades and some of them attract a premium which is why the things can sell for over US$3 million at auction.  Other quirks bring less but are still prized, including the handful of 1966 cars rated (sort of) at 450 hp.  The L72 version of the 427 cubic inch engine was initially listed as developing 450 hp @ 5800 rpm, something GM presumably felt compelled to do because the 396 had been sold with a 425 hp rating and the first few cars built included an air-cleaner sticker reflecting the higher number.  However, the L72 was quickly (apparently for all built after October 1965) re-stickered at 425 hp @ 5600 rpm although the only physical change was to the sticker, the engines otherwise identical.  Chrysler used the same trick when advertising the 426 Street Hemi at 425 hp despite much more power being developed at higher engine speeds and that reflected a trend which began in the mid-1960s to under-rate the advertised output of the most powerful engines, a response to the concerns already being expressed by safety campaigners, insurance companies and some politicians.  Later Corvettes would be rated at 435 hp and it wasn’t until the 1970 model year that Chevrolet would list a 450 hp option (the 454 cubic inch (7.4 litre) LS6) but that was exclusive to the intermediate Chevelle and it remains the highest advertised rating of the muscle car era.  GM did plan that year to release a LS7 Corvette rated at 465 hp, building at least one prototype and even printing the brochures but the universe had shifted and the project was stillborn.

1966 Corvette air cleaner decals from Auto Accessories of America.  
The part number for the 427/450 sticker is #37032.

So, all else being equal, an early-build 1966 Corvette with a 450 HP sticker on the air-cleaner should attract a premium but Chevrolet kept no records of which cars got them and with reproduction stickers available for under US$25, it's obvious some have been "backdated", thus the minimal after-market effect.  Nor is there any guarantee some later-build vehicles didn't receive the stickers at the factory so even the nominal October 1965 "cut-off" isn't regarded as iron-clad, many assembly lines at the time known to use up superseded parts just to clear the inventory.  Not easily replicated however was another rarity from 1966.  That year, only 66 buyers chose RPO N03 (the 36 gallon fuel tank).  Depending on the the engine/transmission combination and final-drive ratio chosen, a Corvette's fuel economy was rated usually between "bad" and "worse" so the "big tank option" did usefully increase the range but it was really aimed at those using their cars in endurance racing.


Kelsey-Hayes cast aluminum wheels for C2 Corvette, the knock off version (option code P48, 1963-1966, top) and the later five-stud (option code N89, 1967, bottom).  They were manufactured by Western Wheel Corporation (a division of Kelsey-Hayes).  The images of the centre-cap components (right) are not to scale.

Available as a factory option on C2 Corvettes between 1963-1967, the Kelsey-Hayes cast aluminum wheels remained visually similar throughout the run but there were several detail differences in finish and, in the final year, a major structural change.  No series production 1963 Corvettes appear to have been factory-fitted with the wheels though they were at the time used on some race-cars (with two rather than three-eared hubs) and some of Chevrolet’s pre-production (the so called “pilot cars”) had them; these were the vehicles used in for the photo-sessions for the original brochures where the wheels appear.  The 1963-1964 run used a natural aluminum finish between the fins with a chrome centre cone; in 1965 the color was changed to a charcoal grey metallic while in 1966 the cone received a brushed finish.  The wheels were attached with “knock off” hubs which gained their name from the use of a hammer to “knock them off” (and back on) when a wheel needed to be removed.  Chevrolet in the tool kit of Corvettes fitted with the wheels included a 2 lb mallet with a lead face & core because damage can result if a steel hammer or mallet is used.  Lead being soft, with repeated use the stuff can wear away and expose the steel cylinder within so periodically the device should be inspected.  The major change came for 1967 when thinner fins appeared and, as a consequence of newly imposed federal regulations, the knock off hubs were replaced with the more familiar five-stud securing arrangement.  In 1967, the option code for the wheels changed from P48 to N89 and, reflecting the lower cost of production entailed in the simpler construction, the price was reduced from US$316.00 to US$263.30 but that added some 6% to the base cost and they were fitted to only 720 of the 22940 (3.14%) 1967 Corvettes produced although many more now exist with reproductions.  The new centre caps came to be known as “Starbursts”.

Starburst sea anemone.

As a noun & verb, “starburst” widely has been used in slang and commerce but its origin is owed to astronomers of the 1830s and in the field it’s been used variously to describe (1) a violent explosion, or the pattern (likened to the shape of a star) supposed to be made by such an explosion and (2) a region of space or period of time (distinct concepts for this purpose) with an untypically or unexpectedly high rate of star formation.  In SF (science fiction), starbursts can be more exotic still and have described machines from light-speed propulsion engines to truly horrid doomsday weapons.  In typography, a starburst is a symbol similar in shape to an asterisk, but with either or both additional or extended rays and it’s used for a brand of fruit-flavored confectionery, the name implying the taste “explodes” in the mouth as one chews or sucks.  In corporate use, starburst is slang for the breaking up of a company (or unit of a company) into a number of distinct operations and in software it was in the early 1980s used as the brand name of an application suite (based around the Wordstar word-processor) which was (along with Electric Office) one of the first “office suites”, the model Microsoft would later adopt for its “Office” product which bundled, Word, Excel, the dreaded PowerPoint and such.  It was the name of a British made-portable surface-to-air missile (MANPADS) produced in the late twentieth century, in botany it’s a tropical flowering plant (Clerodendrum quadriloculare), the term applied also to a species of sea anemone in the family Actiniidae and, in human anatomy, certain cell types (based on their appearance).  In photography, the “starburst effect” refers to the diffraction spikes which radiate from sources of bright light.         

1969 Corvette L88.

The C2 Corvette had a short life of only five years and it would have been shorter still had not there been delays in the development of the C3 which went on sale in late 1967.  Dramatically styled, the C3 eventually debuted for the 1968 model year, the lines reminiscent of the Mako Shark II  (1965) concept car and the coupé included the novelty of removable roof panels.  Underneath the swoopy body, the C3 was essentially the same as the C2 except the old two-speed Powerglide was retired, the automatic option now whichever of the three-speed Turbo-Hydramatics suited the chosen engine.  The C3 also saw one of the early appearances of fibre-optic cables, used to provide an internal display so drivers could check the functionally of external lights and for 1969, the 327 was stroked to 350 cubic inches (5.7 litres), one of the surprisingly large number of changes which can make the 1968 Corvette something of a challenge for restorers, there being so many parts unique to that model-year.  Still available was the L88 and in the two seasons it was offered in the C3, 196 were sold (80 in 1968 and 116 in 1969) but even in its most successful year, the option represented only around .003% of annual production.

C3 Corvette production Count, 1968-1982.

A classic roadster, the C3 Chevrolet Corvette L88: Convertible with soft-top lowered (top left), convertible with hard-top in place (top right), convertible with soft-top erected (bottom left) and coupé (roof with two removable panels (T-top)) (bottom right).  The four vehicles in these images account for 2.040816% of the 196 C3 L88 Corvettes produced (80 in 1968; 116 in 1969) and the L88 count constitutes .000361% of total C3 production.196 C3 L88 Corvettes were produced (80 in 1968; 116 in 1969) and the L88 count constitutes .000361% of total C3 production.

Joan Didion (1934-2021) and cigarette with her Daytona Yellow (OEM code 984) 1969 Chevrolet Corvette Stingray (on the C2 Corvette (1963-1967) and in 1968 the spelling had been "Sting Ray”) The monochrome image was from a photo-session commissioned in 1970 by Life magazine and shot by staff photographer Julian Wasser (1933-2023), outside the house she was renting on Franklin Avenue in the Hollywood Hills.  To great acclaim, her first work of non-fiction, Slouching Towards Bethlehem (1968), had just been published.

Writing mostly, in one way or another, about “feelings”, Joan Didion’s work appealed mostly to a female readership but when photographs were published of her posing with her bright yellow Corvette, among men presumably she gained some “street cred” although that might have evaporated had they learned it was later traded for a Volvo; adding insult to injury, it was a Volvo station wagon with all that implies.  She was later interviewed about the apparent incongruity between owner and machine and acknowledged the strangeness, commenting: “I very definitely remember buying the Stingray because it was a crazy thing to do.  I bought it in Hollywood.”  Craziness and Hollywood were then of course synonymous and a C3 Corvette (1968-1982) really was the ideal symbol of the America about which Ms Didion wrote, being loud, flashy, rendered in plastic and flawed yet underpinned by a solid, well-engineered foundation; the notion of the former detracting from the latter was theme in in her essays on the American experience.

A 1969 Chevrolet Corvette Stingray in Daytona Yellow.

Disillusioned, melancholic and clinical, Ms Didion’s literary oeuvre suited the moment because while obviously political it was also spiritual, a critique of what she called “accidie” of the late 1960s, the moral torpor of those disappointed by what had followed the hope and optimism captured by “Camelot”, the White House of John Kennedy (JFK, 1917–1963; US president 1961-1963).  In retrospect Camelot was illusory but that of course made real the disillusionment of Lyndon Johnson (LBJ, 1908–1973; US president 1963-1969) leading the people not to a “great society” but to Vietnam.  Her essays were in the style of the “new journalism” and sometimes compared with those of her contemporary Susan Sontag (1933-2004) but the two differed in method, tone, ideological orientation and, debatably, expectation if not purpose.

Joan Didion with Corvette, another image from Julian Wasser’s 1970 photo-shoot.  The staging in this one is for feminists to ponder.

While a stretch to say that in trading-in the Corvette for a Volvo station wagon, Ms Didion was tracking the nation which had moved from Kennedy to Richard Nixon (1913-1994; US president 1969-1974), it’s too tempting not to make.  Of the Corvette, she used the phrase: “I gave up on it”, later recounting: “the dealer was baffled” but denied the change was related to moving after eight years from Malibu to leafy, up-market suburban Brentwood.  While she “…needed a new car because with the Corvette something was always wrong…” she “…didn’t need a Volvo station wagon” although did concede: “Maybe it was the idea of moving into Brentwood.”  She should have persevered because as many an owner of a C3 Corvette understands, the faults and flaws are just part of the brutish charm.  Whether the car still exists isn't known; while Corvette's have a higher than average survival rate, their use on drag strips & race tracks as well as their attractiveness to males aged 17-25 has meant not a few suffered misadventure.

Joan Didion with Corvette, rendered as oil on canvas with yellow filter.

The configuration of her car seems not anywhere documented but a reasonable guess is it likely was ordered with the (base) 300 horsepower (hp) version (ZQ3) of the 350 cubic inch (5.7 litre) small-block V8, coupled with the Turbo-Hydramatic 400 (TH400) (M40) three-speed automatic transmission (the lighter TH350 wouldn't be used until 1976 by which time power outputs had fallen so much the robustness of the TH400 was no longer required).  When scanning the option list, although things like the side-mounted exhaust system (N14) or the 430 hp versions (the iron-block L88 & all aluminium ZL1, the power ratings of what were barely-disguised race car engines deliberately understated, the true output between 540-560 hp) of the 427 cubic inch (7.0 litre) big-block V8 would not have tempted Ms Didion, she may have ticked the box for the leather trim (available in six colors and the photos do suggest black (402 (but if vinyl the code was ZQ4)), air conditioning (C60), power steering (N40), power brakes (J50), power windows (A31) or an AM-FM radio (U69 and available also (at extra cost) with stereo (U79)).  Given she later traded-in the Corvette on a Volvo station wagon, presumably the speed warning indicator (U15) would have been thought superfluous but, living in Malibu, the alarm system (UA6) might have caught her eye.    

1969 Corvette ZL1 Roadster.

Uniquely in 1969, there was one option more expensive than the L88, the RPO ZL1, sometimes described as “an all aluminium L88” but actually with a number of differences, some necessitated by the different metal while others were examples of normal product development.  Again the fruit of Chevrolet’s support for the Can-Am teams, the ZL1 was no more suited to street use than the L88 and at US$4,718.35 was three times as expensive.  In 1969, a basic Corvette listed at US$4,781 so if the ZL1 option box was ticked the price essentially doubled although beyond that temptations were few, like the L88, air conditioning, power steering, power brakes and even a radio not available.  It was thus unsurprising demand was muted and it's now accepted that of the seven built, only two were sold, the other five being for engineering and promotional purposes, these “factory mules” scrapped or re-purposed after their usefulness was over.  The yellow coupé last changed hands in October 1991 when it was sold in a government auction for US$300,000 (then a lot of money) after being seized by the DEA (Drug Enforcement Agency) and in January 2023, at auction, the orange roadster realized US$3.14 million.  The yellow ZL1 for years sat in the museum attached to Roger Judski's Corvette Centre in Florida (a hive of DEA activity) but it was on 15 April 2025 announced that after sixty years of service to the Corvette community, Mr Judski was retiring and the centre was closed.

1969 Corvette ZL1 Coupé in Daytona Yellow.

So the orthodox wisdom is there are two “real” ZL1s and an unknown number of faux versions (described variously as clones, replicas, tributes etc, none of these terms having an agreed definition and thus not useful as indications of the degree to which they emulate a factory original).  However, the “ultra” faction in the Corvette community maintains the yellow coupé is a genuine one-off and claim the orange roadster left the factory with an L88 engine and in that form it was raced, as well as when fitted with a ZL1.  The faction further notes the orange machine is an early-build vehicle reported to have closed chamber heads whereas the RPO ZL1s used open chambers.  The “moderate” faction continues to regard the count as two although nobody seems now to support the rumors which circulated for a few years indicating a third and even a fourth, the supposed “black roadster” later confirmed to be faux.  Given all that, the fact the orange car sold for over US$3 million in 2023 does suggest that were the yellow one to go on the block, a new record price would be likely.  Roger Judski (b 1947), owner of the yellow ZL1, was in the Corvette business for sixty years (1965-2025) and is as authoritative an expert on the breed as anyone: he belongs to the moderate faction which supports the orthodox count of two factory ZL1s.

1971 Corvette with RPO ZR2 LS6 454.  This is one of two convertibles, the other 10 1971 ZR2s being coupés.

The 1969 ZL1 and L88 however would prove to be peak C3 Corvette.  Times were changing and in 1970 it was the Chevelle which was offered with Chevrolet’s top big-block street engine, the now 454 cubic-inch (7.4 litre) LS6 rated at 450 hp, the industry’s highest (official) rating of the era; plans for a 460 or 465 hp (both numbers quoted in various internal documents) LS7 Corvette were cancelled as insurance premiums soared and the regulatory environment began to tighten around the high-powered monsters although serious horsepower remained available: while the LS5 454 was rated at 390 horsepower, the performance it delivered suggested it was perhaps a little healthier.  The Corvette highlight of the 1970s however came in 1971 with the availability of the RPO ZR2 for the LS6 engine, described in dealer sheets as the “RPO ZR2 Special Purpose LS6 Engine Package” and it can be regarded as a successor the L88, supplied with the Muncie M22 close-ratio (Rock-Crusher) four-speed manual transmission, transistorized ignition, a heavy-duty aluminum radiator (with shroud delete, a hint it really didn’t belong on the street), heavy-duty power disc brakes, F41 Special Suspension with specific springs, shocks and special front and rear sway bars.  Like the L88s, air-conditioning and a radio were not on the option list, neither much used on race-tracks.  Chevrolet built only a dozen ZR2 Corvettes (two of which were convertibles) in 1971, not because production deliberately was limited but because of the cost (the list price was a then substantial US$7.672.80) and their unsuitability for everyday use meant demand was subdued.  Although scheduled for 1970, industrial relations problems delayed production of the ZR2 until 1971 by which time stricter regulations had compelled cancellation of the LS7 454 so RPO ZR2 was re-purposed for the LS6, rated at a conservative 425 horsepower although this didn’t fool the insurance industry.  

800 cfm (cubic feet per minute) carburetor on 1970 Corvette LT-1.

Lurking behind the thunder of the 454 however was the most charismatic of the small-block Corvettes since the days of the fuel-injected 283 & 327.  This was the 350 LT-1, a high-revving engine very much in the tradition of the Camaro Z28's (in the early days it appeared also as Z-28 & Z/28) 302 cubic inch (4.9 litre) V8 used in the Trans-Am series.  The LT-1 featured heavy-duty internals and high performance additions including solid valve lifters, forged pistons, an 11:1 compression ratio, four-bolt main bearing caps, a forged steel crank, a hi-lift camshaft, a baffled sump and a free-flowing induction and exhaust system.  At US$447.60, the LT-1 option was some 35% more expensive than the big block LS5 454 which listed at US$289.65 (echoes of the days of Rochester fuel-injection), it was almost twice the price of a 454 but was a persuasive package and over three seasons 1287 were made.  Available only with a manual transmission, it lasted until 1972 and although the lowering of the compression ratio meant power ratings dropped season-by-season (1970:370 HP; 1971:330; 1972:255), the 1972 number reflected also the industry's change from quoting gross (SAE) to net (DIN) HP so the reduction wasn't as dramatic as it might appear.  Although still fast by most standards, the 1972 cars were somewhat less potent, the compensation being that by reducing the redline to 5600 RPM, the belt would no longer "fly off" the compressor so the the LT-1 in its final season could be ordered with air-conditioning.  The intricacies of the detail differences (such as the different oil pan used on cars with a CTU engine suffix and the availability of power steering with the CTX engine) mean assessing an LT-1 (there are fakes in the wild) is an exact science and the judging bodies (the best known of which is the NCRS (National Corvette Restorers Society) have codified the process so are able to produce a single "authenticity metric".  They don't insist the brake fluid be original but where possible, everything should be "as delivered".

1970 Corvette LT-1 ZR1; note the metal fan shroud.

Most desirable (for a buyer with specific needs) of the LT-1s were those ordered with the ZR1 package, 53 of which were delivered between 1970-1972.  A US$968.95 option in 1970 (in 1970 the MSRP (Manufacturer's Suggested Retail Price) for the new sub-compact Chevrolet Vega was US$2,090.00), the ZR1 options were focused not on additional horsepower but rather rendering the chassis better suited for use in competition, the target market those who wanted to participate in competitions run by the SCCA (Sports Car Club of America).  Accordingly, what was included was a “cold-air” hood, transistorized ignition, the famed (and noticeably audible) Muncie M22 (rock crusher) four-speed manual transmission, electronic ignition, upgraded power brakes, stiffer shock-absorbers (dampers) & springs and a front anti-sway (stabilizer) bar (despite the existence of some documentation, no ZR1 seems ever to have been factory-fitted with a rear bar).  There was also a larger capacity cooling system with an aluminum radiator, augmented by a metal shroud and fan combination optimized for high-speed operation although the 1972 ZR1s were shroudless.  In an indication of the purposes of many buyers, a popular option was the 4.11 Positraction rear axle (Code G81 @ US$12.65), ideal for drag strips and some race tracks but less suited to highway driving.

1970 Corvette LT-1 ZR1 with factory hard-top (Code C07 @ US$273.85) fitted.

The ZR1 engines did however have detail differences from most of the standard LT-1s, all fitted with the 6 quart (5.7 litre) oil pan (used on the early 1970 LT-1s with a CTU engine suffix, later (CTX) cars using a 5 quart (4.7 litre) version) and a smaller, lighter flywheel & clutch combination (a la the L-88s) while some (apparently restricted to those delivered in California which even then had stricter emission standards) also had a special venting device for the carburetor.  Given the emphasis, choosing the ZR1 package meant that (like the big-block L88 & ZL1), the fitting of luxuries like power windows, power steering, air conditioning, the rear-window defroster, the fancy wheel covers, alarm system and a radio was precluded.  ZR1 buyers inhabited a certain niche and the things are now highly prized.

Not so highly prized: 1980 Corvette (California model with LG4 305 V8) in Frost Beige (paint code 59) over Dark Doeskin leather (trim code 59C).  It looked the part, even if the engine and transmission were shared with station wagons.

The LT1 is fondly remembered but from then on, mostly it was downhill for the C3 although in its twilight years its popularity reached new heights which would have gratified the corporation because it was one of GM's most profitable lines.  In 1975 both the convertible and the (by then much-detuned 454) big-block V8 were cancelled but tellingly, in what came to be called the "malaise era", the C3 enjoyed a long India summer, its performance stellar on the sales charts if not the track and, with no appetite for horsepower, Chevrolet devoted attention to creature comforts, seats and air-conditioning systems much improved.  A sort of nadir is attached to the 1980 models sold in Californian which, because of more stringent emission rules, were fitted only with an automatic transmission and the LG4 305 cubic inch (5.0 litre) engine found often in Impala station wagons and pick-up trucks although it managed to be a little brisker than the Blue Flame original.  The Californian 305 was claimed to generate 180 hp which was actually 15 more than the unfortunate 350 (L48) in the 1975 model (the optional L82 listed with 205 hp).  The method of calculating stated hp changed in 1972 from gross to net so the earlier numbers should not directly be compared with the newer but there's no doubt the Corvettes after the early-1970s were making a lot less power than the tarmac-melting fire-breathers of a few years before and though things had improved by the early 1980s, it wasn't by much.  Both the tamest of the 1975 cars and the 1980 Californian 305 tend to be coupled as the least desired of the breed but, enjoying solid demand to the end, the C3 remained in production until 1982, the last sold the following year.  In fairness to the "malaise era" Corvettes, they should be compared not with an earlier era but with what else was on the market at the time and judged thus, the Corvette was one of the better performers and still offered much for the money, looking good (if something of a caricature) to the last.