Interesting stuff, supposed to be in the production QX50:
The result of all this is an engine that gets 27 percent better fuel economy than Nissan’s 3.5-liter V6, at roughly the same HP and torque. According to Reuters, at a press conference Nissan engineers said the new engine matches turbodiesels in torque, and is actually cheaper to build than modern turbodiesel engines.
The engine will be officially revealed on September 29 at the Paris Motor Show.
The ingenuity of VC-T engine technology lies in its ability to transform itself and seamlessly raise or lower the height the pistons reach. As a consequence, the displacement of the engine changes and the compression ratio can vary anywhere between 8:1 (for high performance) and 14:1 (for high efficiency). The sophisticated engine control logic automatically applies the optimum ratio, depending on what the driving situation demands.