Pinnacle 4-stroke opposed-piston SI engine shows fuel economy improvements of between 30-60% at light loads, 12-30% at medium loads over conventional
April 24, 2012, Green Car Congress – Pinnacle Engines, the developer of a high compression ratio, four-stroke, spark-ignited (SI), opposed-piston, sleeve-valve architecture engine (earlier post) reports that the most basic configuration of its engine has shown improvements in indicated specific fuel consumption (ISFC) of between 30-60% at light load and 12-30% at medium-load compared to a comparably sized conventional poppet-valve technology engine. There is no ISFC improvement at high load.
The results represent a light-load indicated efficiency improvement of 15-30% (up to 40.9%). The company presented these latest test results in a paper at the SAE 2012 World Congress in Detroit.