The 1981 model was nearly unchanged from 1980 and would be the last model year for the second generation Camaro. The Z28 was still powered by a 350 cubic-inch V8, however due to new emissions regulations the engine was now equipped with a CCC (Computer Command Control) unit for the first time. This predecessor to modern engine control modules had an oxygen sensor, an electronically controlled carburetor, a throttle position sensor, coolant sensors, a barometric pressure sensor, a manifold absolute Pressure sensor (MAP), and a check engine light on the dash. The transmission was now equipped with a lockup torque converter, controlled by the CCC as well. The CCC could also be used as a self diagnostic tool. However, as the goal of this change was strictly emissions reduction, horsepower dropped dramatically, to 175 horsepower (130 kW). Moreover, that engine was now only available with an automatic transmission and those who preferred the four-speed stick had to opt for the smaller 165-horsepower 305, which was the only engine offered in Z28s sold in California, and then only with an automatic. Canadian models, however, could still get the 350 and 4-speed combination, and were not equipped with a CCC. Canadian 1981 Camaros were thus identical to 1980 US model.
RS models were dropped this year, but the RS designation would reappear in 1989. Total production had dropped down to 126 139 from a high of 282,571 in 1979, partially due to the performance loss, and partially due to potential would-be buyers awaiting the all-new third-generation Camaro set for 1982 introduction.
Source: Wikipedia, 2011