Ford launched the latest engine in its expanding EcoBoost family at the 2011 Frankfurt Auto Show, back in September.

At only one-liter in capacity, it's the smallest EcoBoost yet, and continues the downsizing trend seen with the other EcoBoost units.

Ford of Europe has now confirmed that the engine will be launched in the 2012 Ford Focus, hitting European roads next month. The U.S. is expected to get the engine in the smaller Ford Fiesta, but would U.S. motorists accept such a small engine in the Focus too?

There's no doubting the technology behind it. It may only displace a liter of fuel and air, and sport only three cylinders, but with gasoline direct injection technology and a turbocharger, it develops up to 125-horsepower.

That, says Ford, is the same as a naturally-aspirated 1.6, but with significantly better fuel economy.

On the European cycle, which usually produces figures around 20-30 percent higher than EPA tests, Ford is claiming average economy of 47 mpg. A lower-powered model with 100-horsepower should get 49 mpg on average. Highway figures could be even higher.

The engine, developed between two of Ford's technology centers in the U.K, is expected to make its U.S. debut in the Ford Fiesta.

That bodes well for both economy and performance, given that like-for-like the Fiesta is over 500 pounds lighter than the equivalent Focus.

At the moment, the most efficient version of each car - the 2012 Ford Focus SFE and 2012 Ford Fiesta SFE - both manage combined economy of 33 mpg, with 40 mpg highway ratings.

Though the U.S. market may not accept a 1.0-liter Focus just yet, a 3-cylinder Fiesta averaging 5 mpg or more over the SFE with equivalent performance really could prove a hit. Unlike the SFE models, it would also provide that economy without the need for a $495 option package.

So are you looking forward to Ford's EcoBoost Fiesta? And if the Focus was ever given the 1.0-liter option, would you consider that model too? Let us know in the comments section below.

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