A gasoline piston engine that can dynamically change its compression ratio —that is, the amount by which the piston squeezes the fuel-air mixture in the cylinder—has long been a holy grail of engine ...

In a conventional piston engine, the compression ratio defines the relationship between the largest and smallest volume of a cylinder - when its piston is at bottom dead centre and top dead centre ...

The Porsche-Hilite technology is comparatively simple, and could be offered to every automaker if and when VCR comes to market. Share on Facebook (opens in a new window) Share on X (opens in a new ...