Concept: Downsized and Supercharged Hybrid Pneumatic Engine for 30%+ Reduction in Fuel Consumption
Green Car Congress
MAY 23, 2009
The HPE was long thought to be a system in which all engine valves had to be actuated in a fully variable manner to allow for two-stoke pneumatic modes and still enable the four-stroke combustion mode. However, this setup adds complexity and cost. [In The concept engine uses the Bosch electro-hydraulic valve system (EHVS).
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