Corvette has always occupied a truly unique niche in the industry, but it was in no way immune from the twin ravaging elements of tightening federal control and dramatically increasing competition from overseas that came to bear in the early '70s. Despite these potentially crippling factors, however, America's Sports Car continued to prosper, warts and all.
As with all 1975-model cars sold in the U.S., Corvettes had to meet stricter emissions standards established by the EPA. In addition to a catalytic converter, every 1975 Chevrolet Corvette also came equipped with several other new emissions components, including something Chevrolet dubbed "Early Fuel Evaporation" or simply EFE. By sharply reducing engine warm-up time the EFE system cut emissions significantly.
There was no denying the toll the myriad array of emissions control equipment took on performance. In addition to adding many pounds of unwanted weight they directly diminished performance by consuming engine power for their own actuation, reducing compression, inhibiting free flow of intake and exhaust gases, and dictating camshaft specifications.
New and ever-increasing safety standards dictated from the nation's capital also took a discernible toll on performance in the '70s. Front and rear impact-absorbing bumpers, already a requirement in 1974, were further strengthened for '75. Underneath the Corvette's front urethane bumper cover was a rather complex plastic honeycomb assembly, and beneath the rear fascia lay a steel and aluminum framework with a pair of chassis-mounted hydraulic shock absorbers.
In theory, at least, the impact-absorbing bumpers prevented damage to the car from low-speed collisions. In reality, damage almost always still resulted and all the added components intended to prevent it added plenty of weight and unwanted additional expense to the Corvette.
The mandated bumpers also strongly influenced styling, necessitating very large overhangs front and rear. Today, fans of the "rubber bumper" Sharks profess to find the front and rear body treatments attractive, and to some they undoubtedly are. Most people however, are probably more used to it than anything else. Even Corvette News, Chevrolet's own in-house Corvette magazine, had trouble finding something positive to say about the required look. Writing in the October/November '74 issue they said "In talking to Corvette owners across the country we have found that most have gotten used to the rear-end design which was introduced in '74."
Besides the steep toll on performance exacted by the endless stream of rules and regulations cascading out of Washington, Corvette also had to contend with increasing competition in the marketplace. As in past years, traditional foes like Jaguar's XKE and the latest from Ferrari were of no great concern, owing to their relatively steep price tags and low production volume. Likewise, Triumphs, MGs, Alfa Romeos, and other diminutive sports cars posed little threat because of their scant production figures and comparatively anemic performance. Beginning in 1970, however, a new challenger for the already tight sports car market had already gained a solid foothold in this country, and by the mid-'70s it was outselling Corvette by thousands of units per year. When Datsun's 240Z came to these shores in 1970 it caused an instant sensation. Offering superbly balanced performance at the bargain price of about $3,500, it evolved into the 260Z and then the 280Z in '75. The Japanese invasion was not in full swing, but it had surely begun in earnest and though many failed to recognize the obvious, the handwriting was clearly on the wall.