The Six-Stroke Engine

Under the hood of almost all modern automobiles there sits a
four-stroke internal combustion engine (ICE). Though the efficiency of
the design has been improved upon significantly in the intervening
years, the basic concept is the same today as that used by the first
practical four-stroke engine built in the 1870s. During every cycle in
a typical car engine, each piston moves up and down twice in the
chamber, resulting in four total strokes… one of which is the power
stroke that provides the torque to move the vehicle. But the automotive
industry may soon be revolutionized by a new six-stroke design which
adds a second power stroke, resulting in a much more efficient and less
polluting alternative.

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