GM Corvette 1963-1982 Repair Guide



The 1963 Corvette Stingray is a complete departure from the Corvettes which preceded it. The body, frame, and front and rear suspensions are all of new design. Engines and transmissions are the only components that were shared with the older models. Stingray body styling evolved from the original William Mitchell Stingray sports/racing car which competed in 1959-60. Fiberglass bodywork was retained, but included a steel, reinforcing framework around the passenger compartment. The convertible model, with or without hardtop, was retained and a new body style added, the fastback coupe. Retractable headlights, rotated by two electric motors, were also a new feature for the Corvette.

The frame is a ladder type with five crossmembers. The wheelbase has been reduced from the 102 in. of previous models to a more compact 98 in., and the rear track shortened by 2 in. This, coupled with component relocation, resulted in a 48/52 percent front/rear weight distribution; a marked improvement over the 53 percent front weight bias of earlier model Corvettes. Overall body height was reduced by 2 in. Front and rear suspensions are both independent and newly designed for the Stingray. The short/long arm front suspension has the upper arm tilted at an angle of 9° for an anti-dive effect under braking. Steering knuckles pivot in ball joints, instead of the king pins and bushings of the early Corvettes. The fully independent rear suspension is sprung with a nine-leaf transverse spring. Universal-jointed axle driveshafts transmit power to the wheels. Steering gear is recirculating ball type and the linkage includes a hydraulic damper. Power steering and brakes both became optionally available for the first time on a Corvette. Brake drums were enlarged and the brakes were made self-adjusting. Air conditioning became optionally available in late 1963.

1964 saw detail body changes: functional passenger-compartment exhaust vents and elimination of the split rear window on the coupe, removal of the non-functional vents on the hood, and new wheel covers. The Muncie four-speed transmission, introduced in mid-year 1963 to replace the Borg-Warner T-10, became the optional four-speed. The solid lifter engines received larger intake and exhaust valves, and horsepower increased from 340 to 365 and from 360 to 375 for the carburetted and fuel-injected engines respectively. Transsistorized, breakerless ignition became optionally available on high performance engines in 1964.

In 1965, the big change was the introduction of four-wheel disc brakes. Braking power and fade resistance were greatly increased over the drum brakes. A flat hood replaced the 1964 hood which had twin indentations and other body changes included restyled wheel covers and functional exhaust vents behind the front wheels. A new version of the 327 cubic inch engine was introduced, the 350 horsepower, hydraulic-cam option. In mid-year, a 396 cubic inch 425 horsepower engine was made available in the Corvette. 396 Corvettes were distinguished by the domed hood required for carburetor clearance. Cars equipped with the 396 received a larger front stabilizer bar and the addition of a rear stabilizer bar. Side-mounted exhausts with chambered mufflers joined the option list in 1965.

The 250, 365, and 375 horsepower engines were dropped in 1966. The 300 horsepower, 327 cubic inch engine became the standard power plant and the standard three-speed transmission was synchronized in all forward gears. The 396 was bored out to 427 cubic inches and offered in two versions, a 425 horsepower and a milder 390 horsepower model. A heavy-duty, four-speed transmission was introduced for use with the high performance 427. Body changes included a new, egg-crate grille, restyled wheel covers, and the addition of backup lights.

1967 body styling changes included a hood scoop on 427 Stingrays, more subdued exhaust vents on the front fenders, and a center back-up light. Wheels were widened 1 / 2 inch to 6 inches and were slotted. The full wheel covers of former models were discarded for trim rings and center caps. The handbrake was changed to the pull-up type, and relocated to the center console. The 300, 350, and 390 horsepower engines remained the same for 1967. A triple-two barrel carburetor setup was added to the 390 horsepower 427 engine which added an additional 10 horsepower. Also, the same carburetor arrangement was added to the former 425 horsepower engine along with large port aluminum cylinder heads and a matching large port intake manifold. The three-two barrel carburetion also added 10 horsepower to this engine.

For the 1968 Corvette, a completely redesigned body and interior were installed on a basically unchanged chassis. Many of the styling features of the new body had been previewed on the Mako Shark show car. Overall body width and height were reduced, while front and rear tread increased with the use of one inch wider wheels. The convertible model was retained and the fastback coupe was replaced with a hardtop model featuring removable roof panels and rear window. Headlights on 1968 and later cars are raised automatically, with vacuum power when the lights are switched on. Wide oval F70-15 tires replaced the 7.75-15 tires of previous years. The two-speed, Powerglide automatic transmission was superseded by the three-speed Turbo Hydra-Matic, a significant improvement for general driving and performance usage. Engines remained the same, except for the addition of the air-injection reactor pump to control exhaust emissions. Corvettes sold in California have been equipped with the A.I.R. system since 1966.

Body styling remained the same for 1969 except for the addition of a Stingray script above the engine exhaust vent. The doors were slightly reshaped, widening the cockpit by one inch at shoulder height. Wheel width was increased to 8 inches, which also increased front and rear tread. The anti-theft ignition, steering, and transmission lock were introduced in 1969, with the ignition switch mounted on the steering column. Side exhausts were offered for the first time on the new body in 1969. Headlight washers were now included in the standard equipment. The small block stroke was increased to give a displacement of 350 cubic inches; however, horsepower ratings remained the same. 427 engine options remained the same for 1969 with the exception of the redesigned L88 engine. The 2nd design L88 used a large-port aluminum intake manifold with a single 850 cfm Holley carburetor, aluminum large-port open chamber cylinder heads, special camshaft with solid lifters, and redesigned HD connecting rods with 7 / 16 rod bolts. Also, the rare ZL-1 427 engine was an option on models of this year. The ZL-1 had the same horsepower rating of the L88 (430 hp) and shared many internal components with the L88. The rarity of the ZL-1 engine comes with the fact that it used an aluminum cylinder block with cast iron cylinder liner sleeves.

A new grille, larger parabolic reflector turn signals, and wheel well flares were added to the Stingray body for 1970. Cast metal grilles were added over the engine compartment exhaust vents and the tailpipe exits were made rectangular. The seats were redesigned, lowering them one inch for more headroom and making the headrests integral. The 427 stroke was increased for 1970 to give a displacement of 454 cubic inches. Triple, two-barrel carburetion was dropped from the big blocks in 1970. A 370 horsepower 350 cubic inch engine, the LT-1, was introduced to answer the need for a solid lifter, high rpm small block engine. The three-speed, manual transmission was discontinued in 1970, and the four-speed transmission and Positraction rear axle were made standard equipment.

Horsepower was decreased in 1971 through an across-the-board compression reduction. The 350 horsepower, hydraulic-cam version of the small block was deleted from the option list.

1972 saw very few changes made to the Corvette. Rated horsepower was again down, due mostly to a new rating system which utilizes net instead of gross power outputs. The audio alarm antitheft system is not a standard item, and the fiber optic light monitors have been discontinued. Only three engines are offered for 1972, two 350 cubic inch engines and one 454 cubic inch engine. There were no body changes, except for the addition of four new colors.

1973 saw the Corvette receive a new front end with a resilient body color bumper. The cool air induction hood covers the windshield wipers, allowing the wiper door and mechanism to be eliminated. New body mounts and extra soundproofing were also added for 1973. GR70-15 steel-belted radial tires are standard equipment. As far as the small-block engines are concerned, the LT-1 engine was discontinued for this model year. The successor to the LT-1 engine was the L82 high performance engine which used the same short block as the LT-1 but through the use of a hydraulic camshaft and a Quadrajet carburetor, the engine was again down on power. The 454 Turbo-Jet was also available with a rating of 275 horsepower.

1974 was a year of very little change for the Corvette. A resilient rear section was added similar to the front system introduced in 1973. Three engines continued to be available, except in California where only the two 350s were available.

Changes to the 1975 Corvette include a catalytic reactor to reduce emissions, a fuel cell-type fuel tank, and the dropping of the 454 engine.

Only one Corvette body style was available for 1976, the convertible was dropped. The Turbo Hydra-Matic 350 replaced the 400 on the base engine. A partial steel underbody replaced the traditional fiberglass, which both improved body strength and heat protection from the exhaust system.

1977 was a year of refinements and a slight appearance change from the 1976 model.

The 1978 Corvette received its most extensive change since its introduction of the current series in 1968 with a new fastback roof line resulting in a new cockpit design and a larger cargo area. A larger 24 gallon fuel cell type fuel tank is used for greater fuel capacity. Increased horsepower and torque ratings are achieved for the special performance engine over the base engine as a result of improvements of the induction and exhaust systems. The base engine uses a Muncie 4-speed manual transmission while the special performance engine uses a Borg-Warner. Both engines use the same Turbo Hydra-Matic transmission.

1979 was a year of very little change with slight refinements of performance and appearance.

In 1980, the Corvette weight reduction plan was initiated. The following components were lightened to reduce the weight of the Corvette: front and rear bumper systems, hood, door panels, windshield and door glass (reduced thickness), selected frame members, and exhaust system. Appearance changes for 1980 include an integral front air dam, deeply recessed front grilles with integral parking lamps, cornering lamps, integral rear spoiler and functional black louvers on the front fenders. Transmission changes include the use of a locking torque convertor with the automatic transmission, and new gear ratios for the 4-speed manual transmission. Engine availability remains unchanged except for California models. California powertrain availability is limited to the new (to the Corvette) 305 engine with an automatic transmission. Miscellaneous components relating to drive train weight loss include the use of an aluminum intake manifold on the L82 engine, stainless steel exhaust manifolds on the 305 California engine, and a new aluminum differential mounting for all models.

The 1981 Corvette has only slight improvements in appearance and convenience items compared to the previous year. Both 350 engines (L48 and L82) and the 305 have been discontinued for 1981. A new L81 350-4 bbl. engine is the only engine available for 1981. The Corvette recorded an industry first this year through the introduction of an FRP (Fiberglass Reinforced Plastic) rear spring which replaces the previous multi-leaf metal rear spring assembly.

In 1982, appearance and convenience item changes are again minimal. The 350 4-bbl. engine has been discontinued and a 350 engine with twin-throttle body fuel injection (TBI) was introduced. The twin TBI system, referred to as "Cross-fire Injection" by the Chevrolet marketing force, is said to improve both throttle response and fuel economy as compared to the previous 4-bbl. carburetion system. Also, a new 4-speed automatic overdrive transmission with a locking torque convertor is the only transmission available in 1982.

Note that Chevrolet continued to sell 1982 Corvettes as 1983 models for approximately eight months of 1983, as there were no 1983 vehicles in production. To confirm this, if your vehicle is in question, please check the VIN code for the build date of your vehicle.

Corvettes have proven themselves in all types of automotive competition, and the Stingray has continued to bear the Corvette standard in many forms of racing. A Stingray coupe won the first race entered in October 1962 at Riverside Raceway. Since then, Corvettes have continued their winning ways in road racing in the SCCA A and B-Production classes. Corvettes have also taken numerous trophies in drag racing, in both the stock and modified classes. Sebring, Daytona, and Le Mans have witnessed many Corvette entries; Corvettes have placed well overall and succeeded in winning the GT class several times at these endurance races. The aerodynamic Stingray has also been utilized several times in setting Grand Touring class records during the Bonneville Speed Weeks. Just recently, a stock-bodied 1968 Corvette roadster equipped with a twin-turbocharged 430 cid big-block engine broke the stock-bodied record at Bonneville with two 240+ mph runs. That racing improves the breed has certainly proved to be true in the case of the Corvette, with many race-proven pieces having become standard equipment or options on production Corvettes.