Chevrolet Corvette

Third generation-C3 (1968–1982) Main article: Chevrolet Corvette (C3) Corvette Stingray Convertible The third generation Corvette, patterned after the Mako Shark II concept car, was introduced for the 1968 model year and was in production until 1982. C3 coupes featured the first use ofT-top removable roof panels. It introduced monikers that were later revived, such as LT-1, ZR-1, and Collector Edition. In 1978, the Corvette’s 25th anniversary was celebrated with a two-tone Silver Anniversary Edition and an Indy Pace Car replica edition of the C3.
This was also the first time that a Corvette was used as a Pace Car for the Indianapolis 500. [26] Engines and chassis components were mostly carried over from the C2, but the body and interior were new. The 350 cu in (5. 7 L) engine replaced the old 327 cu in (5. 36 L) as the base engine in 1969, but power remained at 300 bhp (224 kW). 1969 was the only year for a C3 to optionally offer either a factory installed side exhaust or normal rear exit with chrome tips.
The all-aluminum ZL1 engine was also new for 1969; the special big-block engine was listed at 430-hp (320 kW), but was reported to produce 560 hp (420 kW) and propelled a ZL1 through the 1/4 mile in 10. 89 seconds. There was an extended production run for the 1969 model year due a lengthy labor strike, which meant sales were down on the 1970 models, to 17,316.  1970 small-block power peaked with the optional high compression, high-revving LT-1 that produced 370 bhp (276 kW). The 427 big-block was enlarged to 454 cu in (7. 44 L) with a 390 bhp (291 kW) rating.

The ZR-1 special package was an option available on the 1970 through 1972 model years, and included the LT-1 engine combined with special racing equipment. Only 53 ZR-1’s were built. 1973 Corvette Stingray Coupe In 1971, to accommodate regular low-lead fuel with lower anti-knock properties, the engine compression ratios were lowered which resulted in reduced power ratings. The power rating for the 350 cu in (5. 7 L) L48 base engine decreased from 300 to 270 horsepower and the optional special high performance LT1 engine decreased from 370 to 330 horsepower.
The big-block LS6 454 was reduced from 450 to 425 bhp (317 kW), though it was not used in Corvettes for 1970; it was used in the Chevelle SS. For the 1972 model year, GM moved to the SAE Net measurement which resulted in further reduced, but more realistic, power ratings than the previous SAE Gross standard. Although the 1972 model’s 350 cu in (5. 7 L) horsepower was actually the same as that for the 1971 model year, the lower net horsepower numbers were used instead of gross horsepower.
The L48 base engine was now rated at 200 bhp (150 kW) and the optional LT1 engine was now rated at 270 bhp (200 kW). [12] 1974 models had the last true dual exhaust system that was dropped on the 1975 models with the introduction ofcatalytic converters requiring the use of no-lead fuel. Engine power decreased with the base ZQ3 engine producing 165 bhp (123 kW), the optional L82’s output 205 bhp (153 kW), while the 454 big-block engine was discontinued. Gradual power increases after 1975 peaked with the 1980 model’s optional L82 producing 230 bhp (172 kW).
Styling changed subtly throughout the generation until 1978 for the car’s 25th anniversary. The Sting Ray nameplate was not used on the 1968 model, but Chevrolet still referred to the Corvette as a Sting Ray; however, the 1969 (through 1976) models used the “Stingray” name as one word, without the space. In 1970, the body design was updated including fender flares, and interiors were refined, which included redesigned seats. Due to government regulation,[citation needed] the 1973 Corvette’s chrome front bumper was changed to a 5-mile-per-hour (8 km/h)system with a urethane bumper cover. 973 Corvettes are unique in that sense, as they are the only year where the front bumper was polyurethane and the rear retained the chrome two-piece bumper set. 1973 was also the last year chrome bumpers were used. The optional wire-spoked wheel covers (left) were offered for the last time in 1973. From 1974 onwards both the front and rear bumpers were polyurethane. 1974 Corvette Stingray Coupe In 1974, a 5-mile-per-hour (8 km/h) rear bumper system with a two-piece, tapering urethane bumper cover replaced the Kamm-tail and chrome bumper blades, and matched the new front design from the previous year. 975 was the last year for the convertible, (which did not return for 11 years) and Dave McLellan succeeded Zora Arkus-Duntov as the Corvette’s Chief Engineer. For the 1976 models the fiberglass floor was replaced with steel panels to provide protection from the catalytic converter’s high operating temperature. Stingray 15 model years where the names Corvette, Sting Ray, and Stingray were synonymous. 1977 was last year the tunneled roof treatment with vertical back window was used, in addition leather seats were available at no additional cost for the first time.
The black exterior color returned after a six-year absence. The 1978 25th Anniversary model introduced the fastback glass rear window and featured a new interior and dashboard. Corvette’s 25th anniversary was celebrated with the Indy 500 Pace Car limited edition and a Silver Anniversary model featuring silver over gray lower body paint. All 1979 models featured the previous year’s pace car seats and offered the front and rear spoilers as optional equipment. In 1980, the Corvette received an integratedaerodynamic redesign that resulted in a significant reduction in drag.
After several years of weight increases, 1980 Corvettes were lighter as engineers trimmed both body and chassis weight. [8] In mid-1981, production shifted from St. Louis, Missouri to Bowling Green, Kentucky, and several two-tone paint options were offered. The 1981 models were the last available with a manual transmission until well into the 1984 production run. In 1982, a fuel-injected engine returned, and a final C3 tribute Collectors Edition featured an exclusive, opening rear window hatch. [8] 1980–1982
1980 Corvette Coupe
In 1980, both front and rear bumper covers were restyled with integrated aerodynamicspoilers that resulted in a significant reduction in drag and increased radiator air flow. The hood was also restyled. The crossed-flag emblems disappeared from the front fenders and were revised to a more elongated style on the nose and fuel door. L-82 emblems moved from the hood to the front fenders on cars ordered with the optional high performance engine. This was the finale for the L-82, now producing 230 hp (172 kW) but it could not be mated to a 4-speed, as the manual gearbox was offered only with the base engine.
The speedometer in all cars read to a maximum of 85 mph (137 km/h), mandated by a new and controversial federal law. Air conditioning became standard, as did the tilt-telescopic steering column, power windows, exterior sport mirrors, and the convenience group. New was an optional roof panel carrier that would mount to the rear fastback deck. [31] Many weight-saving components were introduced including thinner body panels and an aluminum Dana 44 IRS (Independent Rear Suspension) differential and crossmember.
The new lighter unit replaced the arguably stronger cast iron GM 10 bolt IRS differential. [30]In line with further weight savings, the aluminum intake manifold associated with L-82 engines since 1978 was now installed in all cars. For the first time, due to California emission considerations, a unique engine application was installed in cars delivered to that state and was mandatory. This motor was a 305 cu in (5. 0 L) V8 engine rated at 180 hp (134 kW), fitted with new tubular stainless steel exhaust manifolds, and mated to an automatic transmission, also mandatory.
The carburetor and ignition timing were controlled by Chevrolet’s new Computer Command Control system. The smaller displacement engine was not available in any other state. California buyers were credited $50 as consolation but had to pay for the California emissions certification which was $250. For comparison, the L-48 350 cu in (5. 7 L) engine, standard in the other 49 states, was rated at 190 hp (142 kW). The base price increased four times during the model year raising the cost of the car by more than $1,200 to $14,345,24.
In 1981, there was only one powerplant available, a 350 cu in (5. 7 L) engine that, like the L-48 base engine the previous year, produced 190 hp (142 kW), but was now designated the L81. The motor was certified in all states and available with manual or automatic transmissions. Chrome air cleaner lids and cast magnesium valve covers dressed up all engines. The stainless steel exhaust manifolds and computer control system introduced on the 305 cu in (5. 0 L) California engines the previous year were now standard, as was an auxiliary electric engine cooling fan.
This, the last C3 available with a manual transmission, so equipped, had a published 0-60 mph in 8. 1 seconds. This model year was the first to use a plastic rear spring, now a Corvette trademark. The spring saved thirty-six pounds, but was limited to base suspensions with automatic transmission. When equipped with Delco’s new optional ETR (Electronically Tuned Receiver) radio with digital clock, the quartz analog instrument panel clock was replaced with an oil temperature gauge. The cast aluminum wheels, optional since ’76, were now ordered on 90 percent of the cars at a cost of $428. New options included a power adjustable driver’s seat and power remote outside mirrors.
In mid-1981 production shifted from St. Louis, Missouri to Bowling Green, Kentucky, and several two-tone paint options were offered. 1982 Corvette Coupe 1982 saw the debut of the “Cross-Fire Injection” fuel delivery system. This TBI (Throttle Body Fuel Injection) was not the type of fuel injection installed previously in some C1 and C2 Corvettes. It utilized two throttle bodies combined with Chevrolet’s computer control system. The engine produced 200 hp (149 kW) and was mated to a new four-speed automatic transmission with torque converters bypass in the top three gears. Compared to the previous Turbo-Hydramatic 3-speed, the new 700-R4 transmission had a lower first and second gear for improved low-end acceleration, and a fourth gear overdrive that would reduce engine RPM by 30 percent at highway cruising speeds, resulting in better fuel economy.
On the downside, the new transmission was not considered a strong unit and proved problematic. The final model C3 Corvette’s published performance numbers were 0-60 in 7.  seconds-the quarter-mile in 16. 1 @ 85 mph (137 km/h). This was the last year for 8-track tape availability and new “cross-fire injection” emblems appeared on front fenders. Nose and fuel door crossed-flags emblems changed to a more squared design. Chevrolet knew this would be the last year of an entire generation of Corvettes and so commemorated the occasion by offering a Collector Edition with separate serial number sequencing, silver-beige paint, unique wheels patterned after the 1967 model’s bolt-on alloys, and an operable rear hatch window.