Ford EcoBoost Engines Photo Gallery
Smaller engines for real mileage
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The reason that all of our cars have awful mileage is that their engines are so huge. you don't need to put a huge engine in a sedan, just something that will get you around town. The fuel efficiency is increasing alongside the size of the engines, so the increased efficiency is less than noticeable.
GM has been using this technology (direct injection combined with turbocharging) in gasoline engines for a while now (i.e. 2007-up Pontiac Solstice, Saturn Sky)