Jonathan Gitlin

The new Infiniti QX50 might not seem the most natural fodder for these pages, but its engine surely is. Just introduced to the world at the Los Angeles Auto Show, the crossover is powered by the world’s first production variable-compression ratio engine. It’s a 2.0L turbocharged four-cylinder called the VC-Turbo, and it represents a huge leap forward for internal combustion engine technology.

By altering the distance that the piston head travels within its cylinder, the VC-Turbo can operate with a compression ratio as low as 8:1 (for maximum performance) or as high as 14:1 (for maximum efficiency). The engine is as powerful as the older naturally aspirated 3.5L VQ V6 in the previous QX50 and makes more torque, but it’s also smaller, lighter, and a lot more fuel-efficient. It can even switch between the Atkinson and regular combustion cycles.