Chevrolet Corvette C3 History: It Saw the End of an Era and Braved a New One
In this installment of Corvette history, we swim with the “Shark,” a name synonymous with the C3 Corvette. This car was met with mixed reviews when it made its debut in 1968 and braved the endless changes in emissions regulations of the ’70s and ’80s. Development of the C3 Corvette began before the big-block C2s even came out! GM and the Corvette’s designers knew that they couldn’t let the C2 have as long a production run as the C1, which ran for 10 years. So, they set up an in-house design competition with one stipulation: have the car ready for the 1967 model year.
Two teams quickly emerged, one lead by Zora Arkus-Duntov and the other by the Chevrolet Engineering Center’s director, Frank Winchell. A mid-engine car had been a conversation topic since the early ’50s, and though these two men’s opinions on specifics differed, both team’s designs revolved around a mid/rear-engine platform. They drew upon inspiration from the Corvair and European cars of the time, like the Porsche 911 and Lamborghini Miura.
Bill Mitchell, one of the integral leaders of the C2 Corvette, wanted in and formed his own design team. The three teams were all fighting the same fight with different styles. Zora and Mitchell pulled from the early Mako Shark I concepts, and Winchell referenced the Corvair. The swooping lines and sharp edges of the concepts made for stunning artistic installations; however, the cars were all proving to be impractical in their design and difficult mechanically. With the limited technology of the times and parts available to them, coupled with cost constraints, none of the teams were able to make a design work, and the mid/rear-engine concepts were scrapped.
Bill Mitchell turned around and solicited the help of designer Larry Shinoda, and together they created a concept that went straight from the drafting table to full-size model. The design was adaptable to work with a front or mid-engine layout and was passed through the Chevrolet’s design department which cranked out the Mako Shark II concept car. It began the auto show circuit in the middle of C2 production, hinting at the Corvette of the future.
The car was receiving mixed reviews. Despite the underpinnings of the car being essentially the same as the tried and true C2, the car was immediately met with problems. The wedged nose and ducktail rear wing created excessive front-end lift (an issue that plagued the early concepts of Frank Winchell). Cooling was also a problem. The narrow body style carried through to the engine bay which heat-soaked the motor. With such a small nose, the radiator was not getting enough airflow, perpetuating the issue. Overheating problems remained a thorn in the side of the C3 from the sale of the first cars all the way to the end of production.
The concept C3s had squeaky roofs due to chassis flex because of the removable one-piece roof. The center roof beam was added to increase rigidity in the roof and thereby created the iconic T-Top. The convertible optioned cars did not have this problem. With these and other issues piling up, the production of the C3 was delayed a whole year to 1968. Once the car officially went on sale, it was apparent that the build quality of the cars was lacking compared to the previous years and other cars on the market. The mixed reviews remained as the styling was criticized for being too extreme and even the T-Tops weren’t as exciting as GM had hoped. A high note was the tremendous straight-line performance numbers of the big-block cars and on-track fun of the sub-400-hp small-block cars.
The 1968-’69 models carried nearly everything over from the C2, with only minor changes to the fit the new design. 1969 did see the arrival of the first ZL-1 car that featured an all-aluminum 427ci big block. The engine was rated by the factory at 430 hp however, according to Corvette Legends and Corvsport, they could actually make more in the neighborhood of 580 hp with the stock manifolds ditched for headers. The crazy engines didn’t stop there. In 1970, the new solid-lifter LT-1 engine was introduced which boosted the C3’s performance such that the Sports Car Club of America (SCCA) deemed it eligible to run in their Class B Production class. Essentially, racing enthusiasts could, if they selected the right options, by a factory-prepped, race-ready Corvette in 1970.
By 1972, the car was getting tamed a bit, with touring and road comfort being the focus. The chrome front bumpers would go away in favor of increase crash safety ratings. The molded bumper and taillights arrived in 1974 for the same reasons. Away went one of the coolest features on any car ever: the vacuum actuated windshield wiper door. Like many other cars in the 70s, big engines were getting choked out by the EPA’s emission’s regulations. The small-block cars made between 190 and 250 horsepower, and the behemoth 454 was down to 275 hp.
Despite early criticism, the car received more praise as time went on, as the typical growing pains of a new car following a highly successful model (the C2) seemed to be wearing off. We considered the LS4 454 roadster models of 1973-74 to be among the “10 Best Muscle Car Buys” in the January 1986 issue of HOT ROD!
Come 1975, and you get the catalytic converter to keep “Captain Planet” happy. A steel floor was added the following year to keep that emissions device from heating up the cockpit. Fast forward to 1978, and to the 25th anniversary of the Corvette; which had fancy silver visual treatments to indicate the celebration. Power accessories like locks and windows started becoming available too.
In the 1980s, tilt columns and A/C became standard equipment, along with more emissions controls. California cars had lower horsepower ratings compared to other states because of pollution legislation. In response to this (and probably to make the car still feel fast) Chevrolet took weight-saving measures with the use of aluminum. In 1981, the only available engine was the 350, and in ’82, the C3’s last year of production, it was outfitted with the infamous Cross-Fire injection.
The ’70s and ’80s were a dark time for the American car market and as demonstrated by the C3 Corvette, Chevrolet and GM did all they could to maintain the badge’s prowess as a desirable performance car. While cars like the Camaro were meeting their demise, the Corvette soldiered on, braved the storm, and came out on the other side.
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