What year was Corvette offered with a 305 cubic inch engine?

In the early 1970's the Corvette was dealt an enormous blow with the implementation of the Federal Clean Air Act. This legislation spawned oversight that would ultimately govern the emissions output of all vehicles manufactured and sold in the United States.

During this time, Corvettes suffered dramatic adversity in horsepower cuts in order to meet the on-going emission requirements. The famed Big Blocks were the first to go before GM began detuning many of its high horsepower small-block offerings. In most cases, the implementation of these changes was enough to keep the Corvette flying below the radar. But finally in 1980, where in California the ERA’s emissions standards far exceeded those that were federally mandated, the Corvette would suffer its biggest blow. The current 350 CID small block offered in all Corvettes across the country, failed to meet California’s strict emissions standards.

If Chevrolet was going to maintain Corvette sales in California, they would have to take drastic measures - GM had no choice but to place a 305 CID small-block in all 1980 Corvettes destined to be sold in California. This was the only year for the 305 engine in a Corvette. With a compression ratio of 8.5:1, horsepower was rated at only 180 @ 4200 rpm, with torque 255 lb.-ft. @ 2000 rpm. All units came with an automatic transmission.

The correct answer: 1980