The smog pump was actually an air pump. The air was injected at the outlet of
the exhaust valves to assure that there was plenty of oxygen to burn any carbon
that came out of the cylinders. This was the 1970's way to reduce carbon
monoxide emissions from the engines. It worked fairly well, although I'm sure
blowing cold air on the valve stems could warp them and increase the amount of
deposits that would build up.
Once computer controlled injection systems, variable electronic timing, and
oxygen sensors in the exhaust sytem were invented, the engine builders used
fuel/air/ignition management to minimize emissions. Then the air pump went the
way of the running board.
Jim Vance
va...@claflinwildcats.com
