An internal combustion engine having a timing device for advancing operation
of
an exhaust valve, and a method of operating the exhaust valve, wherein, for the
case of a conventional automotive engine, the timing device opens the exhaust valve
less than 90 degrees before bottom dead center in a terminal portion of the power
stroke of the engine, but more than approximately 30 degrees before the bottom
dead center. The engine is a four-stroke engine, and the open interval of the exhaust
valve extends from a terminal portion of the power stroke into the exhaust stroke.
The advancement in the opening of the exhaust valve reduces fuel consumption.