For 1971, compression ratios on all Corvette engines dropped due to stricter emission controls in force. The Lt-1 350 was reduced to 330 horsepower, while the base 350 now went to 270 horsepower. The detuned LS5 454 reached a minor 365 horsepower. The LS7 354 was deleted and replaced with an ‘LS6' 454 four-barrel V8 that was rated at 425 horsepower. Though these were still impressive numbers, it wasn't compared to previous Corvette performance.
For 1972, the power drain continued and was even more so exaggerated by a switch from SAE gross to SAE net power ratings. The base 350 only carried 200-horsepower rating, while the LT1 achieved only 255 horsepower. The sole big-block engine, an LS5 454 only achieved an unimpressive 270 horsepower. As part of a club-racing package, only 30 1972 Corvettes were powered by a special ‘ZR1' version of the LT-1 350.
The 1973 Corvette featured a body-colored rubberized front bumper that replaced the chrome strip that had taken precedence on earlier models. Standard for the first time were openings and radial tires, and now side vents were now single, almost vertical. Unfortunately power was reduced again, making the base 350 now rated at 190 horsepower. A brand new optional 'L-82' 350 featured 250 horsepower. Rated at 275 horsepower, the sold 454 was an 'LS4'.
The new nose on the Corvette also showcased with a matching wedge-shaped, body-colored tail for the 1974 model; the response from designers coping with new bumper regulations. 1974 was the final year for the big-block V8.
Only two engine choices were offered in 1975, the base engine being the 350 V8 which achieved only 165 horsepower, and the L82 which only reached 205 horsepower. Both engines exhaled through a catalytic converter. The 1975 Corvette featured a modification to the bumper system that transformed the rear bumper cover into a one-piece molding. For the 1975 model year, Chevy sold 33,836 coupes and 4,629 convertibles.
Production on the Corvette convertible was ended in 1976. The base ‘L48' was now rated at 180 horsepower as engineers were able to learn more about emission regulations, while the L82 350 reached 210 horsepower. Both of these engines exhaled through four-barrel carburetors. Similar to those used on the Camaro and Vega, the Corvette received a new four-spoke steering wheel for 1976; unfortunately this wheel was almost instantly despised by most fans. Also new this year was the newly grained dash with ‘stitching' molded in.
For the 1977 model year, the Stingray lettering was taken off the fenders. The car basically remained the same for this year with the only other change being the steel reinforcements being added to the hood.
Celebrating 25 years in automotive history, the 1978 Corvette featured a tail redesigned with a large wraparound rear window instead of the buttresses that had been one of the coupe's signature design elements for years. Though the new window did enlarge the luggage capacity, it unfortunately didn't open, so loading cargo was a matter of working around the seats. New instrumentation was added to the interior, which featured a lockable glove-box, and the windshield wiper controls being moved to a stalk on the steering column.
The base L48 350 was rated now at 185 horsepower, while a new dual-snorkel intake increased the output of theL82 version to 220 horsepower. The three-speed automatic was optional while standard transmission continued with a four-speed manual. Extremely popular, the 1978 Corvette was definitely not the quickest Corvette, but a total of 40,725 models were produced.
For the 1978 model year two special-edition models were featured. The ‘Silver Anniversary' edition showcased a two-tone silver-on-top/charcoal-on-bottom paint job while the limited-edition Indy Pace Car featured the iconic black-on-top/silver-on-bottom with a deep chin spoiler and ducktail rear spoiler. Buyers were very impressed with the pace car, this being the first time that the Corvette had paced the May classic. Only aout 6,500 pace cars were produced.
For the first time, production was boosted to beyond 50,000 units with the 1979 model. Changes on the exterior of the car were minor, but the main update was in a dual snorkel air cleaner that now fed the L48 350 that boosted output to 195 horsepower. The L82 now reached 225 horsepower with larger valves, a higher-compression ratio and a more efficient exhaust system.
The 1980 Corvette went through an extensive design update along with a weight reduction. Weighing 250 pounds lighter, the '80 Corvette was available in either manual or automatic transmission. The base L48 350 now achieved 190 horsepower in every state except California, while the L82 was rated at 230. In California the 305-cubic-inch V8 only reached 180 horsepower. Sales were decreased to 40,506 units for the 1980 year.
The 1981 Corvette introduced a new, much lighter fiberglass transverse rear leaf spring. The only engine available, the 190-horsepower ‘L81' version of the 350 V8 was all that was offered. Production of the Corvette moved from St. Louis to a new facility in Bowling Green, Kentucky in June of this year.
For the 1982 Corvette, manual transmission was eliminated, and all models were equipped with a four-speed automatic transmission for this year. Following 17 years of absence, fuel-injection was brought back during this model year, this time with the new ‘Cross-Fire Injection', an electronic throttle body system. The new fuel injection system upped the output of the L81 to 200 horsepower. Sales in 1982 ended with a total of 25,407 units.
The 'Collector Edition' was offered in 1982 and featured silver-beige paint, multivaned wheels, unique graphics, a rear glass window that opened hydraulically and bronze-colored glass roof panels.
The 1983 Corvette was radically updated from the previous year. None of the 43 preproduction '1983' C4 Corvettes were ever sold the general public. In March of 1983, Corvette introduced the 1984 model. The new model featured a 96.2-inch wheelbase, cast aluminum suspension components and a larger interior with fully digital instrumentation.
Keeping many of the C3 styling themes, though they were more conservatively expressed, the old coupe's T-tops were exchanged for a single fiberglass section easily removable with a wrench. Access to the engine was easy with the hood being a giant clamshell piece, and the hideaway headlights were now single square units on rotating mounts. Significantly improved from before, everything mechanical on the C4 Corvette was updated. Using composite transverse leaf springs both on the front and the back, the new suspension system was ideal. For the first time the steering was by rack-and-pinion, the brakes were oversized discs. Making for a stiffer structure, the frame itself featured a large aluminum C-section beam. The new C4 also featured huge tires, Goodyear P255/50VR16 unidirectional 'Gatorbacks' on 16-inch wheels. The small-block 350 V8 was carried over and was once again equipped with Cross-Fire throttle body fuel injection that was now rated at 205 horsepower.
The only transmission available at the start of the 1984 model run was the four-speed automatic, but by January of '84 a brand new Doug Nash '4+3' manual transmission was made available with an electronically engaged overdrive on the top three gears. With an amazing total of 53,877 models sold, the 1984 Corvette established itself as the dominant car in showroom stock racing.
For 1985 the Corvette received the new Tuned Port Injected (TPI) version of the 350-cubic-inch small block. The output of the V8 was increased to 230 horsepower due to the new and much more efficient induction system. The ‘L98' engine was joined to a more comfortable suspension resulting in a significantly improved Corvette.
For 1986 the Corvette lineup included a bright yellow version that was used to pace that year's Indianapolis 500. Bosch antilock brakes were also added for the first time, making the Corvette a safer ‘everyday' vehicle. All Corvette coupes received a third brake light that was placed over its rear hatch, while the convertible received one integrated into the rear fascia. A total of 7,315 convertibles and 27,794 Corvette coupes were sold in 1986.
In 1987 the Corvette received hydraulic roller lifters to the L98's valve train which boosted its output to 240 horsepower. Other than that adaptation the Corvette remained basically unchanged. The options list stretched to include a new Z-52 suspension system which gave higher performance with the sacrifice of comfort, along with new electronic tire-pressure monitors.
The 1988 model featured new 17-inch wheels inside P275/40ZR17 tires on the list of options. The L98 was boosted to 245 horsepower with the addition of new aluminum cylinder heads and a revised camshaft with more improved torque characteristics.
For 1989 the new manual transmission was a ZF 6-speed that had a ‘skip shift' feature that forced a shift from first to fourth gear under part throttle conditions to improve fuel economy. A new FX3 selective ride control system for the Z51-equipped coupes was featured, along with new optional fiberglass hardtop for the convertible.
Never available as a convertible, the ZR-1 was the big news for 1990. Designed and build around the Lotus-designed, Mercury Marine-built, all aluminum, 5.7-liter, DOHC, 32-valve LT5 V8, nicknamed ‘King of the Hill', the ZR-1 achieved an astonishing 375 horsepower. That amount of horsepower was reached only when an in-dash key was set in ‘full-power' mode, not the ‘valet' mode which limited it to just 250 horsepower. The ZR-1 only offered one transmission, the ZF six-speed with large P315/35ZR17 tires on very wide wheels. The ZR-1 received widened rear fenders that featured a new rear fascia that was distinguished by squared-off taillights and convex rear fascia. Nearly twice the price of a regular L98-powered Corvette, the ZR-1 was priced at an exorbitant $58,995.
1990 Corvettes featured a new dashboard with greatly improved mixture of both digital and analog instrumentation, better sound systems, improved ventilation, and a driver airbag.
The following year featured a restyling that included a slicker front end that incorporated wraparound foglights, and a new rear fascia that was similar to the ZR-1's. The rear fascia incorporated the third brake light. New wheels were also added to the '90 Corvette. The price of the ZR-1 skyrocketed to $64,138, and became the first GM automobile to carry a price higher that $60K.
The L98 was deleted in 1992 and replaced with new next-generation small-block V8, the LT1. The new engine was rated at 300 horsepower due to significant revisions to the accessory drives, cylinder heads, fuel injection and cooling system. ASR, Acceleration Slip Regulation was a new traction control feature that could be turned off.
With no other sports car ever coming close, on July 2, 1992, the millionth Chevy Corvette, a white 1992 convertible was built.
In 1993 a special 40th anniversary package was featured on both LT1 and ZR-1 Corvettes that basically consisted of badges and special Ruby Red paint. The LT5 engine was refined while the ZR-1 received boosted horsepower that leapt from 375 to an amazing 405. This was most the powerful production Corvette at the time.
1994 Corvettes featured the addition of a passenger airbag along with updated cockpit trim and steering wheel. To improve drivability and to simplify emission control, the LT1 was treated to sequential fuel injection that didn't increase total power output. New five-spoke wheels were added to the ZR-1.
The 1995 Corvette showcased new side gills that set it apart from previous edition. The brakes were improved for the year, along with revised springs, a quieter-running engine fan and de Carbon gas-charged shocks. A Corvette convertible for the third time paced the Indy 500. The final year for the ZR-1 was 1995.
The ZR-1 was replaced with two very unique editions that marked the end of C4 production in 1996. The ‘Collector's Edition' was offered on both coupes and convertibles and consisted mostly of five-spoke wheels, special emblems and Sebring Silver paint. The second was the Grand Sport, which took its name, along with its blue-with-white-stripe paint job, from an early 1960's racing Corvette and featured an amplified version of the LT1 small-block that was called the ‘LT4'. The small-block achieved a very impressive 330 horsepower.
Entering the fifth-generation of Corvettes, the 1997 edition was most wholly new Corvette since 1953. The complete concept of how the car was built was even changed, along with a brand new engine. Rather than like previous models, the '97 Corvette split the transmission off and placed it between the rear wheels in the back of the car to evenly offset the weight of the engine in front. Previous models bolted its transmission directly behind the engine. A radical innovation for the Corvette, this transaxle arrangement had been used on vehicles like the Porsche 928. The wheels and tires were now 18-inchers in the back, and 17s up front, though the suspension itself still used aluminum links and transverse leaf springs, there was no provision for a spare tire since all tires would be of run-flat design.
Relying on engineered wood products to make up part of the floor, the new frame utilized large, hydroformed rails along with a thick backbone for additional strength. Only offered for the year, the hatchback coupe body shared styling themes from the previous two generations of Corvettes though it did have reduced front and rear overhangs as the wheels moved out toward the corners of the vehicle. A less expensive conventional hood replaced the clamshell hood.
Unrelated to any previous Corvette V8, the C5's engine was brand new. Using all the latest production techniques, C5's 'Gen III' ‘LS1' was an all-new, all-aluminum design that still displaced a nominal 5.7 liters and using a single in-block camshaft to drive the two valves per cylinder via pushrods like the old small block. The C5 engine reached an impressive 345 horsepower. The rear-mounted transmissions were either a version of Chevy's own 4L60-E four-speed automatic or the Borg-Warner T56 six-speed manual or
Not much was changed for the 1998 Corvette except for the addition of a convertible model to the C5 Corvette range. The convertible included a trunk that was accessible from outside of the vehicle, a feat that had not been achieved since the 1962. Offered optional for this year was magnesium wheels. Corvette once again paced the Indianapolis 500, this time selling models to the public, in bluish purple.
The 1999 Corvette featured a fixed roof coupe that was much lighter than either the convertible or the hatchback coupe. New for this year to the options list was a head-up display unit that projected major information on the windshield in front of the driver.
The 2000 Convertible dismissed the passenger-side door lock cylinder as the keyless entry system made it virtually unnecessary. Two new exterior colors were also showcased in 2000, Millennium Yellow and Dark Bowling Green Metallic. The new interior color, Torch Red, was also featured, along with new five-spoke forged aluminum wheels.
The following year Chevy introduced the impressive Z06 Corvette for 2001. A high-compression, low-reciprocating-weight version of the LS1, the LS6 competed with the Z06 for 385 horsepower, while shooting its exhaust out a titanium system. Featuring a special FE4 suspension, the Z06 had a stiffer suspension and thicker anti-sway bars in comparison to other C5s. New lightweight wheels and more aggressive Goodyear tires that weren't run-flat in design were also featured. For much less cost, the Z06 matched or exceeded the ZR-1's performance. With an even more flexible and torque-rich engine, the LS1 had an output increase from 345 to 350 horsepower.
The 2003 Z06 was even better, reaching an amazing 405 horsepower that now matched the highest output of the ZR-1. The suspension of the Z06's was retuned to perform even better than previously. A new Electron Blue pain color was featured, along with a sound system revision.
The 50th Anniversary of the Corvette was celebrated in 2003 with the addition of a 50th Anniversary Edition Corvette that offered either an LS1-powered hatchback coupe or convertible. Showcasing a special deep red paint, the new Anniversary edition also featured a selection of new logos along with a new Magnetic Selective Ride Control system. Once again, the 2003 edition was paced at the Indianapolis 500. Regular Corvettes received new standard equipment that included a power passenger seat and a dual-zone climate control system. The Z06 remained virtually unchanged.
2004 did feature several commemorative editions of all three models. The Z06 featured a carbon-fiber hood along with revised shock valving.
Chevy engineers decided to roll all of the best aspects of the C5 and modify them for 2005, rather than starting with a clean slate. The design ideal was to create a vehicle that does more things effectively better than performance cars, and costing two or three times the price. The new Corvette would improve its refinement and performance, while fixing every notable imperfection of the previous generation. New exposed headlamps were featured, a design that had not been done since 1962, alongside a lean grille that created a distinctive ‘face'. To look less disproportionate, the backside of the Corvette was also slimmed down.
A new 6.0 liter ‘LS2' V8 was featured rather than an engine with 350 cubic inches (5.7 liters) of displacement. Output reached an incredible 400 hp and 400 lb-ft of torque now provided performance that was on a level with the world's best from Germany and Italy. The Corvette reached zero to 60 mph in an amazing adrenaline-pumping 4.2 seconds and continuing on to a top speed of 186 mph, according to Chevrolet. Receiving serious upgrades, the standard six-speed manual was also improved. The clutch was now much smoother and lighter with precise shift feel.
Not one suspension part was brought over from the C5, and three suspension setups were available for this model. The optional F55 Magnetic Selective Ride Control suspension automatically adjusts the shock damping rate instantly in response to any changing conditions. The closest thing to ‘Z06-like' performance, the Z51 package included more aggressive dampers and springs, larger cross-drilled brake rotors, larger stabilizer bars and shorter transmission gearing.
Greatly improved on the inside as well, the model featured seats that provided great support along with comfort while offering plenty of headroom to achieve an open and airy cockpit. Easy to remove and install, the standard removable top can be easily handled by just one person.
For 2005 the Chevrolet Corvette C6 convertible received an overhaul of the suspension geometry along with all new bodywork.
Keeping the relatively good fuel economy of the C5 the '06 C6 Coupe had a low drag coefficient and low weight and when equipped with an automatic transmission it achieved 18/27 mpg (city/highway). Slightly better at 18/28, the manual version is outfitted with CAGS, Computer Aided Gear Selection that has been included in all manual transmission since 1989. CAGS improves fuel economy by requiring drivers to shift from 1st gear directly to 4th when at lower RPM's.
A new LS3 engine with increased displacement to 6.2 liters was featured in 2008 and resulted in 430 hp and 424 lb·ft of torque. The 2008 Z06 received the all new TR6060 six speed manual transmission which replaced the T-56. The interior plastic bezel was improved along with the steering rack. Available in limited quantities due to constraints, an optional full leather interior was offered.
A C7 Corvette will debut in 2010 calendar year, according to several issues of Motor Trend magazine.