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 either the Middle Dutch korver & corver (pursuit boat), the construct being corf (fishing boat; literally “basket”) + -ette 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 is 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 for use on the high seas.  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.  Envisaged originally as a blue-water ship, they were allocated mostly to costal duties or the range of activities smaller vessels fulfilled in fleet support.  In the manner of military mission creep, overlap emerged and in some navies there were occasions when newer corvettes were at least a large an 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 firepower of a fleet.  To the British however, they remained 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 were producing 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 be centred on the ever smaller torpedo boats and the two work-horses of the fleets, the frigate and the 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, the corvette as a designation has essentially become extinct but there have long been frigates and fast patrol boats in service with many navies 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.

1953 Corvette.

The haste 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 thus 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 produced 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 and optimized and 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 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 heavyweight machines 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 and one aborted project was the Grand Sport (GS) Corvette, a competition oriented model.  It had been intended to build a run of 125 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 had been built; all survived and are now expensive collectibles, something which had inspired the creation of a number of clones.

1963 Corvette.

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 1953-1952 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.  One quirk of the 1963 coupés was the split-window design of the rear glass.  A source of debate within Chevrolet, the anti-split faction eventually won and a single piece of glass was 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 to that of the 1964's single piece of glass and many cars were converted.  That changed decades later when the unique feature of the 1963 car made it a much prized collectable and another small-scale industry briefly flourished converting them back and, whether true or urban myth, it’s said as many as 4% of the split-window coupés which now exist may be later models with a bit of judicious back-dating.  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.

1965 Corvette 396 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. 

Mid-year, 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.  Given the numbers, it wasn't surprising only 771 chose the fuel injected 327 compared with the 2157 who opted for the big-block 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) and all these prices 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 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 could provide 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 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.

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 lowest outputs.

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 1969 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 much 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 trend would accelerate; in 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 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.    

Same L72 engine, different stickers: An 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.  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$20, 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).

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.  

1969 Corvette ZL1 Roadster.

However, there was one even more expensive option, 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 and 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 one sits now in the museum attached to Roger Judski's Corvette Centre in that hive of DEA activity: Florida.

1969 Corvette ZL1 Coupé.

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, has been trading Corvettes since 1965 and is as authoritative an expert on the breed as anyone and 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 465 hp LS7 Corvette were cancelled as insurance costs 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 LT1.

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 LT1, a high-revving mill very much in the tradition of the Camaro's 302 Z/28 (RPO Z28 picked up the slash when used as a model name) used in the (five litre (305 cubic inch) production car) Trans-Am series, which 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.  In a echo of the days of Rochester fuel-injection, it was almost twice the price of a 454 but was a persuasive package and over a thousand were made.  Available only with a manual transmission, it lasted until 1972 and although the lowering of the compression ration meant power ratings dropped season-by-season (1970:370 HP; 1971:330 HP; 1972:255 HP), the 1972 number reflected the industry's change from quoting gross to nett horsepower 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 (to stop the belt flying off the compressor), the LT1 could that year be ordered with air-conditioning.  Most desirable of the C3 LT1s were those ordered with the ZR1 package, fewer than 60 of which were delivered between 1970-1972.  The ZR1 options were focused not on additional horsepower but rendering the chassis better suited for use in competition, the target market those who wanted to participate in the racing series run by the SCCA (Sports Car Club of America).  Accordingly, what was included was a cold-air hood, a larger capacity cooling system (including a different shroud and fan optimized for high-speed operation), the famed Muncie M22 (rock crusher) four-speed manual transmission, electronic ignition, upgraded power brakes, stiffer shock-absorbers (dampers), springs and front & rear anti-roll (sway) bars.  Given the emphasis, choosing the ZR1 package meant that, like the big-block L88s & ZL1, the fitting of luxuries like air conditioning, the rear-window defroster, power steering, the fancy wheel covers, alarm system and a radio were precluded.  ZR1 buyers really did inhabit a niche market and the vehicles are now 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.

The LT1 is fondly remembered but from then on it was mostly downhill for the C3 although in its last years its popularity reached new heights and 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 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 nett 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 fondly remembered 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.