The Outlander PHEV has a 2.4L 16-valve inline 4 cylinder engine. It has a supremely efficient Atkinson-cycle with a long expansion stroke. This makes it much more efficient, so it offers better fuel economy and less emissions. This is a type of internal combustion engine invented by James Atkinson in 1882. It increases the efficiency of a four-stroke spark ignition by minimising the intake of fuel during the intake stroke or expansion stroke.
