If you know much about how engines work, the idea of a variable compression ratio seems almost crazy. The idea isn't new, in fact Saab claims to have been working on it since the 1980s, but it's never ...

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 ...

European automakers are trying to wring every possible fuel-economy advance from gasoline engines to meet upcoming tougher European Union carbon dioxide emission levels. The technology push already ...