Chevrolet Corvette (C3)
The Chevrolet Corvette is the third generation of the Corvette sports car that was produced from 1967 until 1982 by Chevrolet for the 1968 to 1982 model years. Engines and chassis components were mostly carried over from the previous generation, but the body and interior were new. It set new sales records with 53,807 produced for the 1979 model year. The C3 was the second Corvette to carry the Stingray name, though only for the 1969–1976 model years. This time it was a single word as opposed to Sting Ray as used for the 1963–1967 C2 generation. The name was then retired until 2014 when it returned with the release of the C7.
The most expensive Corvette C3 to sell in history was a 1969 L88 Lightweight, one of only four lightweight L88s to be produced. It was sold by Barrett-Jackson in January 2014 for $2,860,000.
History
Mako Shark II Concept
The Corvette C3 was patterned after the Mako Shark II designed by Larry Shinoda. Executed under Bill Mitchell's direction, the Mako II had been initiated in early 1964. Once the mid-engined format was abandoned, the Shinoda/Mitchell car was sent to Chevrolet Styling under Dave Holls, where Henry Haga's studio adapted it for production on the existing Stingray chassis. The resulting lower half of the car was much like the Mako II, except for the softer contours. The concept car's name was later changed to Manta Ray. The C3 also adopted the "sugar scoop" roof treatment with vertical back window from the mid-engined concept models designed by the Duntov group. It was intended from the beginning that the rear window and that portion of the roof above the seats to be removable.The "Shark" has the distinction of being introduced to the motoring public in an unorthodox—and unintended—fashion. GM had tried their best to keep the appearance of the upcoming car a secret, but the release of Mattel's die-cast Hot Wheels line several weeks before the C3's unveiling had a certain version of particular interest to Corvette fans: the "Custom Corvette", a GM-authorized model of the 1968 Corvette.
1968–1969
For 1968, both the Corvette body and interior were completely redesigned. As before, the car was available in either coupe or convertible models, but the coupe was now a notchback fitted with a near-vertical removable rear window and removable "T-top" roof panels. A soft folding top was included with convertibles, while an auxiliary hardtop with a glass rear window was offered at additional cost. Included with coupes were hold down straps and a pair of vinyl bags to store the roof panels, and above the luggage area was a rear window stowage tray.The new body's concealed headlights were operated by an engine vacuum system rather than electrically as on the previous generation, and the new hide-away windshield wipers utilized a problematic vacuum door. The door handles were flush with the top of the doors with a separate release button. Front fenders had functional engine cooling vents. Side vent windows were eliminated from all models, replaced with "Astro Ventilation", a fresh air circulation system. In the cabin, a large round speedometer and matching tachometer were positioned in front of the driver. Auxiliary gauges were clustered above the forward end of the console and included oil pressure, water temperature, ammeter, fuel gauge, and an analog clock. A fiber-optic system appeared on the console that monitored exterior lights. There was no glove box. The battery was moved from the engine area to one of three compartments behind the seats to improve weight distribution. New options included a rear window defroster, anti-theft alarm system, bright metal wheel covers, and an AM-FM Stereo radio. As with the C2 cars, all cars ordered with a radio were to be fitted with chrome-plated ignition shielding covering the distributor to reduce interference.
The chassis was carried over from the second generation models, retaining the fully independent suspension and four-wheel disc brake system. The engine line-up and horsepower ratings were also carried over from the previous year, as were the 3- and 4-speed manual transmissions. The new optional Turbo Hydramatic 3-speed automatic transmission replaced the two-speed Powerglide.
The standard engine was the L30, a small-block V8 engine rated at. It was available with a 3-speed manual transmission, but only a few hundred were sold equipped this way. The more popular option was a 4-speed manual, available in M20 wide-ratio or M21 close-ratio versions. The M22 "Rock Crusher", a heavy duty, close-ratio 4-speed gearbox, was also available for certain applications. Also available was the L79, a high performance version of the small-block.
Also available were several variants of the big-block V8 engine that, taken together, made up nearly half the cars. There was the L36, a version with a Rochester 4-barrel carburetor; The L68, a motor with a Holley triple 2-barrel carb set up ; The L71, generating at 5,800 rpm and at 4,000 rpm of torque also with a tri-power; The L89 option was the L71 engine but with lightweight aluminum cylinder heads rather than the standard cast iron. Then there was the L88 engine that Chevrolet designed strictly for off-road use, with a published rating of, but featured a high-capacity 4-barrel carb, aluminum heads, a unique air induction system, and an ultra-high compression ratio of 12.5:1.
All small block cars had low-profile hoods. All big block cars had domed hoods for additional engine clearance with twin simulated vents and "427" emblems on either side of the dome. The new seven-inch wide steel wheels had F70x15 nylon bias-ply tires standard with either white or red stripe tires optional. Rare options were: L88 engine, J56 heavy-duty brakes, UA6 alarm system, L89 aluminum heads.
In 1969, small block engine displacement increased from to, though output remained the same. All other engines and transmission choices remained unchanged from the previous year, though the L30 base engine was now the ZQ3 and the L79 motor was redesignated the L46. All cars featured steel wheels. Tire size remained the same, although this was the first year for optional white lettered tires and the last for red striped tires. Carried over from the previous year were seven available rear axle ratios ranging from 2.73 to 4.56. Standard ratio remained 3.08 with automatic and 3.36 with manual transmission. The optional Positraction rear axle, mandated on many engine/gearbox combinations, was installed on more than 95% of the cars. "Stingray" script nameplates appeared on front fenders, now one word, in contrast to the "Sting Ray" name used previously. Exterior door handles were redesigned so the finger plate would actuate the door, eliminating the separate release button. Backup lights were integrated into the inboard taillights, headlight washers were added, and front grilles were made all black. Side-mounted exhausts and front fender vent trim were options for this year only. On the inside, revised door panels provided additional shoulder room in the C3's tighter cabin and headrests became standard. Steering wheel diameter was reduced from 16 to 15 inches to permit easier entry and exit, the ignition switch was moved from the dash to the steering column, and map pockets were added to the dash area in front of the passenger seat. Accounting for 57% of the cars, coupes with their removable roof panels, began a trend of outselling roadsters. An extended production cycle due to a labor dispute increased 1969 volume. This was the last year for the L88 engine and the only year for the ZL1 option, which offered an all-aluminum big-block engine listed at. Rare options: ZL1 aluminum block, J56 heavy-duty brakes, L88 engine, L89 aluminum heads.
Car and Driver magazine wrote in October 1968, "The small-engine Corvettes are marginally faster and extraordinarily civilized. The large-engine Corvettes are extraordinarily fast and marginally civilized."
1970–1972
With January 1970 production, fender flares were designed into the body contours to reduce wheel-thrown debris damage. New were eggcrate grills with matching front fender side vents and larger squared front directional lamps. The previously round dual exhaust outlets were made larger and rectangular in shape. Interiors were tweaked with redesigned seats and a new deluxe interior option combined wood-grain wood accents and higher-spec carpeting with leather seat surfaces. Positraction rear axle, tinted glass, and a wide-ratio 4-speed manual transmission were now standard.The base engine remained at and the L46 was again offered as a high performance upgrade. New was the LT1, a small-block V8 engine delivering a factory rated. It was a solid lifter motor featuring a forged steel crankshaft, 4-bolt main block, 11:1 compression ratio, impact extruded pistons, high-lift camshaft, low-restriction exhaust, aluminum intake manifold, 4-barrel carburetor, and finned aluminum rocker covers. The new engine, making up less than 8% of production, could not be ordered with air conditioning but was fitted with a domed hood adorned with "LT1" decals.
Motor Trend in May 1970, clocked an LT1 covering the quarter mile in 14.36 seconds at 101.69 mph and remarked, "There is Corvette and there is Porsche. One is the best engineering effort of America, the other of Germany. The difference in machines is not as great as the disparity in price."
A special ZR1 package added racing suspension, brakes, stabilizer bars, and other high performance components to LT1 cars. Big-block selection was down to one engine but displacement increased. The LS5 was a motor generating SAE gross and accounted for a quarter of the cars. The LS7, which was equipped with a single 800 CFM Holley carburetor and advertised at at 5600 rpm SAE gross and at 3600 rpm of torque, was planned and appeared in Chevrolet literature but is not believed to have ever been delivered to retail customers, but offered as a crate engine. A short model year resulted in a disproportionately low production volume of 17,316, down nearly 60%. Rare options: ZR1 special engine package, shoulder belts in convertibles, LT1 engine.
Produced from August 1970, 1971 cars were virtually identical in appearance to the previous model inside and out. This was the final year for the fiber optics light monitoring system, the headlight washer system, and the M22 heavy duty 4-speed manual gearbox. For the first time, air conditioning was installed on most of the cars, with nearly 53 percent so ordered. Engines were detuned with reduced compression ratios to tolerate lower octane fuel. The small blocks available were the base engine, which dropped to, and the high performance LT1, now listed at. The LS5 motor was carried over and produced. Offered in ‘71 only was the LS6 big-block featuring aluminum heads and delivering, highest of the 1970–1972 MYs, and could be ordered with an automatic transmission. The ZR1 option was carried over for LT1 equipped cars and the ZR2 option, offered this year only, provided a similar performance equipment package for LS6 cars, and restricted transmission to a 4-speed manual. Rare options: ZR1 special engine package, ZR2 special engine package, LS6 425 hp engine, shoulder belts in convertibles.
1972 was the last model year for chrome bumpers at both front and rear, the vacuum actuated pop-up windshield wiper door, as well as the removable rear window common to all 1968–1972 coupes. The key activated anti-theft alarm system became standard. The increasingly popular choice of an automatic transmission was installed in most Corvettes for the first time, with nearly 54 percent so equipped. This year SAE net measurement for horsepower was now utilized, and was largely responsible for the much lower engine output figures such as the rating on the standard motor. This was the final year for the LT1 engine, rated at, and the ZR1 racing package built around it. Although the M22 HD 4-speed was no longer a Regular Production Option, it continued to be fitted to cars outfitted with the ZR1 package. The LT1 could now be ordered with air conditioning, a combination not permitted the two previous years. The LS5 big block was again available and came in at. In 1972 the LS5 was not available to California buyers. This was the beginning of a trend where Chevrolet restricted certain power train choices to California buyers due to that state's practice of applying more stringent emission standards than mandated by federal regulations. Convertibles were a vanishing breed by ‘72, and the Stingray was no exception. It sold only 6,508 copies, amounting to 9% of the market, placing it number three; it was beaten by the number one-selling Cutlass Supreme, with 11,571, but beat the Impala's 6,456 and the Mustang's 6,401. Rare options: ZR1 special engine package, shoulder belts with convertibles, LT1 engine option.