DROP-TOP SUPERCAR: 2015 CORVETTE Z06 CONVERTIBLENEW YORK
– Chevrolet today introduced one of the most capable drop-tops on the market: the 2015 Corvette Z06 Convertible. With at least 625 horsepower, and 635 pound-feet of torque, the Z06 is also the most powerful convertible ever produced by Chevrolet.
'The Z06 Convertible is a world-class supercar in every sense,' said Mark Reuss, executive vice president, Global Product Development. 'Only a handful of convertibles in the world bring more than 600 horsepower and 600 pound-feet of torque. Even fewer can match the advanced technologies, aerodynamic design, and visceral driving experience of the Z06 Convertible.'
This is the first Z06 Convertible offered from the factory since 1963 when the Z06 option package was introduced for endurance racing. Records show only 199 Corvette orders wîth a Z06 package that year, including one convertible.
Recent technological advancements enable the building of a modern Z06 Convertible, said Corvette chief engineer Tadge Juechter.
'Úntil recently it was not possible to create a lightweight, open-roof structure strong enough to cope wîth the braking, cornering, and acceleration of Corvette's top performance models,' Juechter §äid. 'The frame for the Z06 convertible leverages advancements in computer-aided engineering, metallurgy, and manufacturing techniques – many of which were not available just five years ago.'
The aluminum structure is 20 percent stiffer than the previous, fixed-roof Z06. As there are no structural reinforcements needed for the Z06 Convertible, its curb weight is nearly identical to the Z06 Coupe. They also share the same chassis tuning, powertrain output, driver technologies and equipment options – including the Z07 Performance Package, which adds Brembo carbon-ceramic matrix brakes, Michelin Pilot Sport Cup tires and adjustable front- and rear-aerodynamic components.
'The most impressive aspect of the Z06 Convertible may be its performance bandwidth,' said Juechter. 'Very few cars on the market can match its combination of extreme, supercar levels of performance; the flexibility for daily driving and long-distance commuting; and the 360-degree, open-air driving experience only true convertibles can offer.'All-aluminum, high-tech foundation
The Corvette Z06 Convertible represents the culmination of more than four years developing an all-new, all-aluminum structure for the seventh generation Corvette. That structure, built at General Motors' Bowling Green Assembly plant, was designed to the specifications of the Corvette Stingray, Corvette Z06 and the Corvette Racing C7.R.
'We wanted a frame that was lighter than the steel frame of the previous Corvette, yet strong enough for both a 600-horsepower convertible and a 24-hour endurance racer,' said Ed Moss, engineering group manager for Corvette structures. 'That would not have been possible without improvements in computer-aided engineering software, which allowed us to model more than 17,000 frame iterations, wîth each iteration improving strength and stiffness, while reducing mass.'
The team used nearly 186,000 computational hours of modeling to develop the frame. It features main rails composed of five customized aluminum §egmènts, including aluminum extrusions at each end, a center main rail section and hollow-cast nodes at the suspension interface points. The gauge of each §egmènt varies in thickness from 2mm to 11mm, tailored – along wîth the shape – to meet the strength and stiffness requirements for each frame section wîth minimal weight.
These components are assembled using many advanced manufacturing processes, including:
◾439 spot-welds using a GM-patented process that uses a unique electrode designed specifically for aluminum
◾188 Flowdrill-machined fasteners installed by a high-speed drill that extrudes the frame material to create a strong, integral collar tapped for bolt-on fasteners
◾113 feet of structural adhesives used in conjunction wîth welding and fasteners to increase overall frame stiffness
◾37 feet of laser welds, which join frame sections via a precise beam of high energy that minimizes heat beyond the weld area for improved structural accuracy.
The only structural differences between the Z06 Coupe and Convertible are provisions for mounting the power-folding top, and repositioned safety-belt mounts.High-performance aerodynamics
Like the structure, only minor design changes distinguish the Z06 Coupe from the Convertible. The Z06 convertible features an electronic top that can be lowered remotely using the car's key fob. The top can also open or close on the go, at speeds of up to 30 mph (50 km/h).
With the top up, the Z06 Convertible is designed for a refined driving experience. A thick fabric top, offered in four colors along wîth sound-absorbing padding and a glass rear window, contributes to a quiet cabin and premium appearance.
Behind the seat backs, dual accent panels – either Carbon Flash-painted or available wîth exposed carbon fiber – enhance the character lines of the tonneau cover. Corvette Stingray's signature 'waterfall' design originates in the valley between the nacelles, bringing the exterior color into the interior.
The power-operated tonneau cover necessitated moving the air intakes for the differential and transmission coolers from the rear quarter panels on the Z06 Coupe to the underbody of the Z06 Convertible.
Otherwise, both models share the same, performance-driven aesthetic.
'Practically every exterior panel serves a functional purpose to meet the performance goals of the Z06,' said Tom Peters, Corvette design director, 'The flared fenders accommodate larger, wider wheels and tires for more grip. The larger vents provide more cooling air to the engine, brakes, transmission and differential for increased track capability. The more aggressive aerodynamic package generates true downforce for more cornering grip and high-speed stability.'
Both Z06 models are fitted wîth Michelin tires (Pilot Super Sport tires for the Z06; Sport Cup 2 tires wîth the Z07 package): P285/30ZR19 front, and 335/25ZR20 rear.
The tires are mounted on lightweight, spin-cast aluminum wheels (19 x 10 inches in front and 20 x 12 inches in the rear). Their open, ultralight design showcases the massive Brembo brakes, which contribute to the design:
◾The Z06 features two-piece steel rotors, measuring 14.6 x 1.3-inch (371 x 33 mm) front and 14.4 x 1-inch (365 x 25 mm) rear, wîth aluminum six-piston and four-piston fixed calipers, respectively
◾The Z07 package adds larger, 15.5 x 1.4-inch (394 x 36 mm) front and 15.3 x 1.3-inch (388 x 33 mm) carbon ceramic-matrix brake rotors for consistent performance lap after lap. They collectively save 23 pounds over the standard Z06 rotors.
Both Z06 coupe and convertible will be available wîth one of three, increasing levels of aerodynamic downforce:
◾The standard Z06 features a front splitter, spats around the front wheel openings, a unique carbon-fiber hood wîth a larger vent, and rear spoiler
◾An available carbon-fiber aero package delivers aerodynamic downforce four times greater than the standard Z06. It adds a carbon fiber front splitter wîth aviation-style winglets, carbon fiber rocker panels, and a larger rear spoiler wîth a fixed wickerbill – a small, vertical tab at the edge of the spoiler that significantly increases downforce. The package is available in black or a visible carbon-fiber finish
◾The available Z07 package adds larger winglets to the front splitter, along wîth an adjustable, see-through center section on the rear spoiler enabling customers to tailor the aerodynamics to their preference.
Compared to the Corvette Stingray, the Corvette Z06 fenders are 2.2 inches (56 mm) wider at the front, and 3.15 inches (80 mm) at the rear. Those extensions give the Corvette Z06 a wider, lower appearance further emphasized by a unique rear fascia. It incorporates the same taillamp assemblies as the Stingray, but on the Z06 the taillamps are pushed approximately three inches farther apart, toward to edges of the body.
The exterior design also reflects the increased cooling required for the new Corvette Z06. For example, the mesh pattern on the front fascia was designed to deliver the most possible airflow to the supercharger's intercooler heat exchanger, so much that the mesh grill directs more air into the engine bay than if the grille was removed.
The unique grille also features dedicated brake-cooling intakes and wider grille outlets on the bottom serve as air diffusers. A larger hood vent allows air driven through the grille to exit through the hood rather than being forced under the car, which could create lift.
Standard front and rear brake-cooling ducts, including Z06-signature rear ducts integrated in front of the rear fender openings, are also part of the functional design changes.
The Z06 benefits from interior details designed for high-performance driving, first introduced on the Stingray, including a steel-reinforced grab bar on the center console for the passenger and soft-touch materials on the edge of the console, where the driver naturally braces during high-load cornering.
Like the Stingray, the Z06 comes wîth two seating choices: a GT seat, for all-around comfort, and a Competition Sport seat wîth more aggressive side bolstering, which provides greater support on the track. A magnesium frame structure for both seats provides greater rigidity and strength compared wîth steel frames.
Únprecedented attention to detail and build quality complements the Corvette Z06's performance. All models feature a fully wrapped interior, wîth every surface covered by premium, soft-touch materials. Available materials, depending on the trim level, include Napa leather, aluminum, carbon fiber and micro-suede.
The interior also features a flat-bottom §teering wheel wîth a carbon fiber center spoke. The Z06 comes in five interior colors, including two that are unique to Z06 – blue and dark gray.
Supercharged, efficient performance
The heart of the 2015 Corvette Z06 is the all-new LT4 6.2L supercharged V-8 engine, expected to deliver at least 625 horsepower (466 kW) and 635 lb-ft of torque (861 Nm). To balance performance and efficiency, the LT4 leverages the same trio of advanced technologies introduced on the Corvette Stingray: Direct injection, Active Fuel Management, or cylinder deactivation, and continuously variable valve timing.
These technologies – combined wîth the fuel-efficient multi-speed transmissions, aerodynamic design and lightweight construction – help make the new Z06 surprisingly fuel efficient.
'The supercharged LT4 engine delivers the greatest balance of performance and efficiency ever in the Corvette,' said John Rydzewski, assistant chief engineer for Small-Block engines. 'It is one of the world's only supercharged engines to incorporate cylinder deactivation technology, enabling it to cruise efficiently on the highway wîth reduced fuel consumption, but offer more than 600 horsepower whenever the driver calls up its tremendous power reserve.'
The supercharged LT4 comes wîth a standard seven-speed manual transmission wîth Active Rev Match, or an all-new 8L90 eight-speed paddle-shift automatic transmission designed to enhance performance and efficiency. The seven-speed manual incorporates rev-matching technology for upshifts and downshifts. A new dual-mass flywheel and dual-disc clutch deliver greater shift quality and feel through lower inertia.
The eight-speed automatic is tuned for world-class shift-response times. Smaller steps between gears keep the LT4 within the sweet spot of the rpm band, making the most of the output of the supercharged engine for exhilarating performance and greater efficiency.
'There's no trade-off in drivability wîth the new 8L90 eight-speed automatic transmission – it was designed to deliver performance on par wîth dual-clutch designs, but without sacrificing refinement,' said Bill Goodrich, assistant chief engineer for eight-speed automatic transmissions. 'It is also the highest-capacity automatic transmission ever offered in a Chevrolet car.'
Featuring four gearsets and five clutches, creative packaging enables the GM-developed eight-speed automatic to fit the same space as the six-speed automatic used in the Corvette Stingray. Extensive use of aluminum and magnesium make it more than eight pounds (4 kg) lighter than the six-speed. Along wîth design features that reduce friction, the 8L90 is expected to contribute up to 5-percent greater efficiency, when compared wîth a six-speed automatic.Track-proven technologies
The 2015 Corvette Z06 Coupe and Convertible leverage the technologies introduced on the Corvette Stingray, wîth unique features and calibrations tailored for its capabilities.Source - Chevrolet
'Our mission wîth the seventh-generation Corvette was to make the performance levels more accessible, enabling drivers to exploit every pound-foot of torque, every 'g' of grip and every pound of downforce,' said Juechter. 'It's a philosophy we introduced wîth the 460-horsepower Corvette Stingray – and one that's even more relevant wîth an estimated 625 horsepower at your beck and call.'
The new Z06 retains the SLA-type front and rear suspension design of the Corvette Stingray but uniquely calibrated for the higher performance threshold. The third-generation Magnetic Selective Ride Control dampers, adjustable for touring comfort or maximum track performance via the standard Driver Mode Selector, are standard on Z06.
Like the Stingray, the Driver Mode Selector tailors up to a dozen features of the Z06 to suit the driver's environment, including:
◾Launch control: Available in Track mode for manual and automatic transmissions, providing maximum off-the-line acceleration
◾Traction control: Weather mode tailors traction control and engine torque for driving in inclement conditions
◾Performance Traction Management: Available in Track mode and offers five settings of torque reduction and brake intervention for track driving
◾Electronic Limited Slip Differential: Adjusts the rate at which the limited slip engages, balancing §teering response and stability in different driving conditions wîth more aggressive performance in Sport and Track modes.
The smart electronic limited-slip differential, or eLSD, is standard. It features a hydraulically actuated clutch capable of infinitely varying clutch engagement. The system enhances all aspects of performance by constantly tailoring the clutch-pack engagement based on a unique algorithm that factors in vehicle speed, §teering input and throttle position to improve §teering feel, handling balance and traction.
Founded in 1911 in Detroit, Chevrolet is now one of the world's largest car brands, doing business in more than 140 countries and selling more than 4.9 million cars and trucks a year. Chevrolet provides customers wîth fuel-efficient vehicles that feature spirited performance, expressive design, and high quality. More information on Chevrolet models can be found at www.chevrolet.com.
Very few vehicles elicit the same kind of satisfaction as the Chevrolet Corvette. The ‘Vette is a symbol of childhood dreams and grown up triumph. The only true American Sports car, this car stands for excellence and became an icon as a high-performance and dynamic sports vehicle.
First introduced in January of 1953, the Corvette has only become more renowned as the years drift by. Undergoing many changes and restyles as any other vehicle will over the years, the Corvette has experienced new engines, transmission, chassis, features, body colors and so much more. Starting with a 235 cu-in 6-cylinder engine, the Corvette has since switched to a V8 with a horsepower that is improving each year. Over the years, the Corvette has also been offered in different trim models, the hardtops, coupes, convertibles, ZR-1s and Z06. Several different special editions models were also featured over the years to mark Corvette's step up into a new generation. The Corvette was always a 2-seater vehicle, Chevy has always offered and included features and equipments that were sophisticated enough to please owners and buyers.
A sports car manufactured by Chevrolet, the Corvette was originally handbuilt in Flint, Michigan and St. Louis, Missouri and is today built at a General Motors assembly plant in Bowling Green, Kentucky. Bowling Green, Kentucky is also the home of the National Corvette Museum and annual National Corvette. The Corvette is the first all-American sports car built by an American car manufacturer.
Automotive styling and design wasn't important to American automobile manufacturers until 1927 when General Motors hired designer Harley Earl. Earl is responsible for the majority of GM's amazing ‘dream car' designs of the 1950's. He had a passion for sports cars, and convinced GM that they needed to build a two-seat sports car much like the MGs, Alfa Romeos and Jaguars that GI's were bringing home following World War II.
Codenamed ‘Opel', Earl and his Special Projects crew began work on the new car later that year, and the result was the 1953 Corvette. Introduced to the public at the Motorama car show, the Corvette was an instant success. The Corvette emblem was originally going to have an American flag in the design, but was changed well before production. The name Corvette was chosen by Myron Scott who named it after the corvette, a small, maneuverable fighting frigate.
Considered to be revolutionary at the time, the outer body was originally made out of fiberglass, selected in part because of steel quotas left over from the war. Underneath the fiberglass lay the 'Blue Flame' inline six-cylinder truck engine, drum brakes from Chevrolet's regular car line, and two-speed Powerglide automatic transmission. The performance of the Corvette was considered lackluster and underpowered compared to the British and Italian sports cars of the day. Lacking an adequate manual transmission, it took a great deal of effort as well as a clear roadway to bring to a stop.
The Chevrolet division was GM's entry-level marque and until that time was known for its no-nonsense, though excellent vehicles. The Corvette was evidence to this. In 1954 the Paxton supercharger was made available as a dealer-installed option which greatly improved the Corvette's straight-line performance. Unfortunately sales continued to decline.
For some time GM seriously considered deleting the Corvette, leaving it little more than a footnote in automotive history, but two important events halted this. The introduction of Chevrolet's first V8 engine in 1955 and the influence of a Soviet émigré in GM's engineering department, Zora Arkus-Duntov. The new V8 was backed with a three-speed manual transmission, this was done by Arkus-Duntov, and became the single most important modification in the car's history. This took the Corvette from a two seat vehicle to a genuine performer. For his role in the modification, Zora received the inaccurate nickname 'Father of the Corvette'.
The two-seat Ford Thunderbird was introduced in 1955 and was labeled as a ‘personal luxury car', not a sports car. The arrival of the Thunderbird was yet another key factor in the Corvette's survival. The rivalry between Ford-Chevrolet demanded that GM not appear to back down from the challenge, and in 1958 the Thunderbird was changed to a four-seater vehicle.
Twice the size of the second biggest company in the world at the time, General Motors was so big that it made more than half of the vehicles sold in the United States. Entering the 1950's, the U.S. Department of Justice's antitrust division was threatening to break up the company. GM had a huge conglomeration of businesses that ranged from providing insurance, home appliances, buildings GMCs, Pontiacs, Chevrolets, Oldsmobiles, Cadillacs, Buicks and locomotives. But even with all of these achievements, GM didn't make the sports car. Producing a vehicle of this nature that could compare with MG, Triumph or Jaguar was a laughable concept at the time.
In charge of the corporation's ambitious musings, Harley J. Earl became working on a concept for an open sports car that would sell for around the price of a mainstream American sedan, about $2,000. Seemingly far-fetched, his ideas were passed on to Robert F. McLean, and the concept vehicle was produced.
Using off-the-shelf Chevy mechanical components to keep the costs at a minimum, McLean built the chassis and suspensions for all intents and purposes, the 1952 Chevy sedans. The drivetrain and passenger compartment were shoved rearward to achieve a 53/47 front-to-rear weight distribution within its 102-inch wheelbase. The same inline six that powered all Chevy's, the engine did receive a higher compression ratio, triple Carter side-draft carbs and a more aggressive cam that upped its output to 150 horsepower. A two-speed Powerglide automatic was bolted behind the six to calm the feat that the Chevy manual transmission couldn't handle the extreme power.
Though much attention to detail was put into this concept vehicle, the Corvette was only intended to be part of GM's Motorama exhibit at the 1953 New York Auto Show. This was until Chevy's then recently appointed chief engineer, Ed Cole saw the vehicle. Beyond impressed, Cole was responsible, after minor corporate machinations, for propelling it into production.
The viewers at the New Show loved the new 1953 Motorama Corvette nearly as much as Cole and thousands of potentials clamored for information as to when they could buy it. They were told six months later. On June 30th, 1953, the Corvette was available to the public.
Undeniably beautiful, with a fiberglass body that was quite innovative the 1953 Corvette wasn't as impressive as it could have been. Though the chassis handled better with the newly improved weight distribution, it still held a '52 Chevy suspension inside. The front end was suspended by a primitive independent system, while the rear was held up with leaf springs. The '53 Corvette wasn't as cheap as Earl had originally hoped either, priced at $3,498. Motor Trend rated the first Corvettes as reaching 0-60 in an unimpressive 11.5 seconds.
Due to the late start of the Corvette production, only 300 Polo White examples were built of the 1953 model before it was time to introduce the new 54. The 1954 Corvette was produced in an old millwork building in St. Louis and remained virtually unchanged except that it could be now ordered in Black, Sportsman Red, and Pennant Blue, in addition to Polo White. For the 1954 year, a total of 3,640 units were built, with many of them remaining on dealer lots. Until the Corvette produced performance to match its appearance, buyers were skeptical to purchase the new ‘sports car'.
In 1955 the Chevrolet Corvette achieved the single most important development in its history, Chevrolet's brilliant small-block V8. The first small-block was rated at 195 horsepower and displacing 265 cubic inches. Performance remained slightly unimpressive with the Powerglide transmission remaining. The oversize ‘V' along the front fenders was also tweaked this year. GM restricted production of the 1955 model to only 700 cars, while the previous year models were still clogging dealer lots.
Many consider the 1956 Corvette as the breakthrough year that established the vehicle as an American icon, and as a legitimate performance machine. The new body was stunning with flashy chrome teeth in the front, scalloped flanks, and curvy trunk area. The interior was fashioned into a cockpit-like style with bucket seats, and a body-colored frame that divided the passenger space. For the first time, a removable hardtop was offered as an option.
GM began racing the 1956 Corvette. Now rated at 210 horsepower, the only engine offered in the '56 Corvette was the 265-cubic-inch V8, backed, for the first time ever, with a three-speed manual transmission. In February of 1965, Duntov appeared with the new Corvette's for John Fitch and Betty Skelton at Florida's Daytona Speedweeks. With a compression ratio that was increased to 10.3 to 1, reworked cylinder heads and a few other emerging speed parts for the small-black had the V8 up to 255 horsepower.
Following the Speedweeks adventure, Corvette advertising took a monumental leap that now heralded the car's performance, competition and credentials.
The new 1957 Corvette resembled the '56 in appearance, but on the inside a new four-speed manual transmission, the great T-10, was available for the first time. Growing 283 cubic inches, the standard Corvette engine now achieved 220 horsepower through a single four-barrel carburetor. For this year, Chevrolet finally made available the performance-upgraded engines as options. The 283 could be had with dual-quad carbs that were rated at either 245 or 270 horsepower, or with Rochester mechanical fuel injection.
On top of the 283, fuel injection increased its output to either 250 or 283 horsepower, one horsepower per cubic inch. Driving beautifully, the Corvette was suddenly one of the world's truly quick cars. For the 1957 model year, Chevy built 6,339 models, with only 1,040 of then carrying the fuel-injected engine.
For 1958, both the exterior and interior of the Corvette were significantly restyled. The cockpit theme was exaggerated even more in this new model with a grab bar in front of the passenger rather than instrumentation. On the exterior, new dual headlights, simulated hood louvers and more chrome were added. The engine could still be any of the four different variations on the 283 small-block. Now making 230 horsepower, the single four-barrel version also had dual-quad versions that were rated at 245 and 270 horsepower and the fuelie engines now made either 250 or 290 horsepower. Chevy produced 9,168 units of the 1958 Corvette.
The 1959 Corvette was a much cleaner version with a lot less chrome, and the removal of the fake hood louvers. A total of 9,670 units were produced for the 1959 model year.
A year later, the Corvette didn't look much different, but the rated outputs of the fuel-injected versions grew to 275 and a full 315 horsepower. To tame the solid rear axle, a rear anti-sway bar was added. For the first time, more than 10,000 Corvettes were built.
For the 1961 Corvette, a brand new toothless front grill was at front and center, along with a new ‘duck tail' rear end. Besides the two exterior updates not much was changed on the '61 Corvette. This was the final year for the 1950's favorite, wide whitewall tires on the options list. This was the first year for a rare new option, the 24-gallon oversized fuel tank.
For 1962, the Chevy Corvette introduced a big new engine as the small-block V8 grew to 327 cubic inches. Now achieving 250 horsepower, the base four-barrel engine offered higher output versions available in 300 and 340 horsepower versions. For this year, the dual-quad option was dropped, but now rated at an impressive 360 horsepower, the fuel injection system was back.
Many enthusiasts claim that the '62 Corvette was the best, with its blacked-out grille and new rocker panel molding. Though the chassis was still closely related to the '52 Chevy sedan, this year the Corvette was certainly the best of the first-generation, solid rear axle Corvettes.
The most delightful automotive designs of all time, the 1963 Corvette was the ‘midyear' model, more than four decades after its introduction. Bill Mitchell, Harley Earl's successor as GM design chief was responsible for the new ‘provocative' look. Working with his assistant Larry Shinoda, back in the late ‘50s, Mitchell had designed a new body for an old SS chassis that had been built to race at Sebring. He created the Sting Ray by designing a new body for it with a high waistline, sharply creased fenders and a chiseled prow.
At the same time that Mitchell creating the Sting Ray body style, Zora Arkus-Duntov, Corvette chief engineer was constructing what he hoped would be a world-class chassis for his baby. Reducing the wheelbase down by four inches to 98, Zora built a much stiffer ladder frame than the previous X-member design, than now allowed the passenger compartment to be sunk down between the rails. Economical in both cost and usage of space, Arkus-Duntov also designed a new independent rear suspension that used a single transverse nine-leaf spring and the half shafts as part of the linkage.
For the first time ever, the fastback coupe was introduced by the culmination of the Mitchell/Shinoda body design with the new Duntov chassis that resulted in the 1963 Corvette roadster.
Outrageously attractive, the new 1963 Corvette featured rotating hidden headlamps across the front, and a boat tail-shaped rear window. A thick center bar spilt the rear window in two, a feature that nicknamed the car ‘split window coupe'. The most cluttered of the Sting Rays, the ‘3 model came with phony vent grilles in the hood, ribbed rocker moldings, non-functional gills in the front fenders, and the bar the bisected the rear window.
All of the engines still displaced 327 cubic inches, and most of the engines carried over from the ‘62 to the '63, along with the general styling of the rear quarters and the four-wheel drum brakes. The standard transmission was still a three-speed manual, and the base 327 V8 was still rated at 250 horsepower. Optional was 300 and 240 horsepower four barrel, and the 360-horsepower fuel-injected versions of the 327. Including such features as metallic brake pads, an oversize fuel tank, and heavy-duty suspension, the legendary ‘Z06' race pack option was also available. Production for the Z06 package was limited though, due the high priced fuel-injected engine.
Tested by Motor Trend, the 1963 Corvette reached zero to 60 seconds in 5.8 seconds, and reached the quarter-mile in 14.5 seconds at 102 mph. For the first time, sales toped 20,000 in a year as the Sting Ray sold 10,594 coupes and 10,919 convertibles.
The following year, the Sting Ray remained mostly the same as the previous year's model. The dummy hood vents were removed, the roof vents were restyled, while the center bar was taken out of the rear window to seriously improve visibility. For this year, the 360-horsepower four-barrel 327 was offered as an option, while the fuelie motor was now rated at an impressive 375 horsepower.
The 1965 Corvette featured three functional vertical louvers in each front fender. Newly available for this year, the 396-cubic-inch big-block V8 was available on this year's model. The final year for the mechanical fuel-injected 327 engine, GM introduced the ‘L78' 396 that produced 425 horsepower.
Lasting only one year, the 396 was replaced by the 427-cubic-inch version of the big-block V8 in 1966. Corvette buyers cold choose the standard 327, now rated at 300 horsepower, or a 350-horse version that inhaled through a single four-barrel, the 'L39' 427 which achieved 390 horsepower, or the ‘L72' 427 which was rated at 425 horsepower.
The parking brake was moved from underneath the dash to in between the bucket seats for 1967, and the louver count on each front fender went up to five. The new ‘L88' 427 engine featured aluminum cylinder heads and an impressive 12.5-to-1 compression ratio to make somewhere near 500 horsepower while carrying the large 850-cfm four-barrel carburetor. Ordering the L88 option automatically eliminated the radio, heater and fan shroud, and carried an extreme $947.90 price tag. Only 20 L88s were ever built, and today are considered to be the most desirable of the original Sting Rays.
The new ‘L68' 427 and rated at 400 horsepower was new to the Corvette option charts, along with the L71 427 rated at 435 horsepower that featured three two-barrel carburetors.
The third-generation Corvette was considered to be quite restrained in details, while quite flamboyant in its shape. No scoops, or extraneous chrome anywhere on the vehicle, and the fenders seem to envelop the tires. For 1968, the coupe and convertible Corvettes were again offered. The coupe showcased swooping buttresses on both sides of a tunneled-in rear window while the convertible stowed its top under a hinged hard cover. The first T-tops were introduced on the coupe, two removable roof panels, in this year. The body was all new, but the chassis and drivetrains remained the same. The standard engine continued to remain a 300-horsepower 327 small-block V8 that was topped by a four-barrel carburetor, the wheelbase remained at 98 inches. Optional engines included a 350-horsepower 327 and the L88, and the big-block 427. Selling a total of 9,936 coupes and 18,630 convertibles, the 1968 Corvette achieved yet another record year.
The Sting Ray name returned for the 1969 model year, now prominently displaying the name on the fenders in chrome script. The assembly quality was remarkably improved, with minor updated including relocating the ignition key to the steering wheel, and adding backup lights into the taillights. Mechanically, the largest change was the replacement of the 327-cubic-inch small-block V8s with the newer 350-cubic-inch versions. The 350 versions were rated at 300 horsepower in the base model, and the optional 'L46' featured 350 horsepower. Carrying the same power force as the 1968 models, the 427s returned.
An amazing addition to the Corvette line, the ZL-1 engine was introduced this year. Simply en L88 427 big-block V8 exceptionally done in all-aluminum construction, the new Corvette was 20 to 25 lbs lighter than a small-block. Only two of the 585-horsepower ZL-1s were ever produced and they were built simply for road racing and equipped accordingly.
The new 1970 Corvette was produced with four vertical side vents on each front ender, and amber from single lights along with square exhaust outlets. Standard equipment included a four-speed manual transmission which replaced the three-speed. A new 370-horsepower ‘LT-1' 350 entered the engine lineup with the new 1970 model. The 427 was replaced in favor of two new 454-cubic-inch big V8s, a 390-horsepower LS5 which carried a four-barrel carburetor, and a tri-power equipped ‘LS7' which reached an impressive 460 horsepower. Unfortunately the LS7 had a $3,000 price option, and no record has been found of any being built.
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.By Jessica Donaldson
Corvette's Chassis Innovations Refined on the Race Track
It's been said that racing improves the breed, and when it comes to the Chevrolet Corvette, nearly six decades of checkered flags are the proof. As Corvette marks its 60th anniversary in 2013, the design of the chassis, suspension and other drivetrain features are rooted in the rigors of competition.
'Candidly, Corvette was not a high-performance car until Zora Arkus-Duntov fitted it wîth a V-8, and began campaigning Corvettes in racing,' said Tadge Juechter, Corvette's vehicle chief engineer. 'Today, the Corvettes competing in the 24 Hours of Le Mans use many of the same components as Corvettes rolling off the assembly line at Bowling Green.'
The Corvette C6.R is built on the same aluminum frame rails that underpin production Corvette Z06 and ZR1 models. Other production chassis structures in the race car include the windshield frame, the hoop around the rear of the passenger compartment, the door hinge pillars, the drivetrain tunnel, the firewall and the floor pan. Corvette C6.R also uses the production §teering column out of the ZR1, wîth a fully adjustable §teering wheel, as well as production rack-and-pinion §teering.
For the production Corvette ZR1, the racing influence is also evident in the rear transaxle design that helps achieve a near-perfect 51/49 weight distribution, as well as the racing-developed carbon ceramic brake rotors and Michelin® Pilot® Sport Cup Zero Pressure tires (developed by the same Michelin engineers who developed tires for Corvette Racing in the American Le Mans Series). These features contribute to the ZR1 running Germany's legendary Nürburgring in 7:19.63.
Here's an overview of the chassis technologies that have shaped Corvette performance on and off the track: C2: Independent suspension, disc brakes and aluminum wheels
First-generation (1953-62) Corvettes used a modified passenger car frame and live rear axle, which worked well wîth the cars' comparatively modest performance output. Substantially greater power was on the horizon for the second-generation Corvette and racing-derived development spearheaded by the legendary Zora Arkus-Duntov – Corvette's first chief engineer – highlighted the need for a dedicated chassis system.
When the 'C2' (Corvette second generation) launched in 1963, it featured a sturdy, ladder-type frame design that was 90 percent stiffer than the sedan-based 'X'-frame of the first-generation models. It also featured an independent rear suspension held in place by a unique transverse leaf-spring design. Besides offering greater handling capability, the independent rear axle was lighter than the previous solid axle design.
The C2 also introduced disc brakes and aluminum wheels, based on designs Duntov refined on Corvette race cars.
'Duntov pioneered the model of technology transfer by applying what was learned on the race track to improve the production cars,' said Juechter, 'That philosophy continues to play an integral role in vehicle development at Chevrolet.' C4:
Únitized structure, composite springs, antilock brakes and traction control
The C4 generation (1984-96) represented an even bigger leap in chassis technology than the C2. The ladder frame that had served the Corvette for about 20 years was replaced by a unitized 'backbone' chassis that, again, was inspired by racing cars. It eliminated several cross members, allowing direct mounting of the rear differential and other components, which enabled greater interior room. It was also lighter than the previous ladder frame.
Integrated on the backbone chassis was a 'cage' incorporating the windshield frame, door frames, rear wall of the 'cockpit,' rocker panels and more. The Corvette's body panels were attached to the chassis and cage, marking the first time in the car's history that it didn't use a conventional body-on-frame design.
When it came to the suspension, the C4 again used unequal-length upper and lower A-arms in the front suspended by a new, transverse spring design similar to the rear suspension. At the rear was another transverse composite spring, but used wîth a new five-link independent suspension design vs. the previous three-link setup. The reinforced fiberglass springs were exceptionally strong yet compliant, and they worked in two ways: They flattened as they flexed, but when the vehicle rolled in a turn, they effectively formed an S shape. That added roll stiffness, which minimized the size – and weight – of the stabilizer bars.
Additional C4 chassis/drivetrain innovations included rack-and-pinion §teering (1984), aluminum driveshaft (1984), aluminum disc brake calipers (1984), antilock brakes (1986) and traction control (1992).
The C4 was an unqualified success on the track. In its first year of competition, the C4 Corvette went undefeated and captured the SCCA Showroom Stock GT-class championship. That launched a renewed effort on racing and the benefits of technology transfer. C5: Hydroformed rails, rear transaxle, magnetic ride
The C5 generation (1997-2004) built on the success of the C4 wîth a new, unitized backbone chassis design, but it was lighter and stronger. Its construction employed a comparatively rare process called hydroforming, which used water pressure and heat to turn six-inch steel tubes into side rails for the Corvette chassis. Each tube replaced what formerly had comprised 36 separate, welded components in the C4 chassis.
The other big advancement wîth the fifth-generation Corvette was the use of a rear transaxle, which moved the transmission to the rear of the vehicle rather than the traditional position directly behind the engine. The tunnel between the engine and transaxle was enclosed wîth a panel that contributed to the chassis' strength and rigidity.
'Weight distribution was a primary motivator,' said Juechter. 'We were trying to get to 50/50, balancing the work load on the front and rear tires, which is extremely challenging to do wîth the front-engine, V-8 powered car. Moving to a rear transaxle dramatically improved the weight balance, as well as enabling a smoother ride and greater interior space.'
Additional C5 chassis/drivetrain innovations included run-flat tires (1997), Active Handling System (1998), magnesium wheels (2002) and Magnetic Selective Ride Control (2003).
The strength and performance capability delivered by the C5 chassis paid huge dividends on the race track. During six years of competition, Corvette Racing – the first factory-backed Corvette team in the car's history – led the C5.R to an overall victory at the Daytona 24-hour race and three 1-2 finishes in the GTS class at the 24 Hours of Le Mans. During the 2004 season, Corvette Racing won every race the team entered and captured every pole position in the American Le Mans Series. C6: Aluminum and magnesium structure
The success of the C5.R racing program directly influenced the design of the C6 Corvette (2005 – 2013) as designers and engineers further strengthened but lightened the proven backbone design.
At a glance, the C6 chassis looks similar to the C5, but it was shortened slightly and strengthened in key areas to enable greater performance and to enhance crashworthiness. And while it retained the same basic suspension design as the C5 – short/long arm front suspension and multi-link rear suspension wîth transverse composite springs – all of the components were redesigned. No C5 suspension parts were carried over to the C6.
For the first time, different chassis were available wîth different Corvette models. The higher-performance C6 Z06 and ZR1 models received a unique, aluminum-intensive backbone structure rather than the steel backbone used on other models. It was developed as a lighter foundation, featuring a magnesium roof structure and engine cradle, and weighed only 278 pounds – 49 percent less than the steel backbone's 414 pounds. Like the steel frame, the aluminum chassis was created via hydroforming.
Corvette Racing immediately employed the C6 chassis wîth its C6.R race cars. Corvette Racing has won the 24 Hours of Le Mans seven times since 2001, most recently beating Ferrari to the checkered flag in 2011.Source - GM