Nissan supercharged and direct-injected three-cylinder engineEnlarge Photo
Hot on the heels of its new dual injector engine comes another relatively unique engine design from Japanese automaker Nissan. The latest innovative design consists of a compact 1.2-liter three-cylinder gasoline engine with direct fuel injection and supercharger technology, boosting output to what Nissan claims is equivalent to that of a 1.5-liter mill.
The engine also benefits from the adoption of the Miller cycle and a fuel saving stop-start system. By adopting the Miller cycle, in which the power stroke is enhanced by the compression stroke as a result of delaying the closing timing of the intake valve, the thermal energy of the fuel is converted to kinetic energy much more efficiently than it is with regular four-stroke cycle engines, and pumping loss caused by intake manifold negative pressure has been reduced.
Additionally, the supercharger can be switched on or off, which means that both high fuel efficiency and high engine performance can be achieved by automatically switching off supercharging while driving at low speeds, such as on city roads, and then on again for high load situations.
The 1.2-liter engine will first appear in the European Micra sub-compact in the first half of next year, a car that Nissan eventually plans to launch in some variation in the U.S. next year as well. Nissan hopes that it will have the lowest fuel consumption in the world for gasoline-powered cars, but Fiat’s recently revealed two-cylinder engine should give it a run for its money.