Crower's Six-Stroke Engine

Crower Cams & Equipment
http://www.crower.com/

Achieving a means of harnessing engine heat, Bruce Crower's internal combustion engine adds two strokes involving the injection of water, which immediately turns to steam, expanding the chamber for another cycle. Process keeps engine running cool.

Technology Description
The first four strokes are the same as an internal combustion engine.

In Crower's design, after the exhaust cycles out of the chamber, rather than squirting more fuel and air into the chamber, his design injects ordinary water. Inside the extremely hot chamber, the water immediately turns to steam, expanding to 1600 times its volume, which forces the piston down for a second power stroke. Another exhaust cycle pushes the steam out of the chamber, and then the six-stroke cycle begins again.

No Cooling System Required
"Besides providing power, this water injection cycle cools the engine from within, making an engine's heavy radiator, coolant, and fans obsolete. Despite its lack of a conventional liquid cooling system, his bench engine is only warm to the touch while it is running."

Potential Efficiency
Crower estimates that eventually his six-stroke engine could improve a typical engine’s fuel consumption by as much as forty percent.

Source links:
http://www.damninteresting.com/?p=467
also
http://peswiki.com/index.php/Directory:Crower's_Six-Stroke_Engine

Further reading:
Autoweek article on the six-stroke engine
Wikipedia article on Internal Combustion Engine
Crower Cams & Equipment homepage

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