Honda has been caught in the patent, well before the jerked it from the public eye, with a new patent on an engine with different displacement sizes on a four cylinder engine. This would allow for cylinder shut-off resulting in the potential of having an engine running in 15 different displacement configurations for maximum economy or power. Very interesting. Read more at: AutoGuide.com or AutoBlog.com. Only time will tell if it every gets used in production models. Below are several patented designs that did not.
GM actually filed for patent on a Variable Displacement Piston Engine in 1979 by changing the displacement through a variable stroke length mechanism, but it never caught on.
Read more about GM’s design at: www.google.com/patents/US4270495.
Honda later cited GM’s patent when it came up with a variable stroke method of its own, but also , to my knowledge, never implemented it into a production model car: www.google.com/patents/US20090288641.