A three-cylinder engine? It's been more than a decade since we've seen one, but now Ford is bringing a three-banger to America.

It's going to be a 1-liter turbocharged three-cylinder engine that will launch worldwide, including the U.S., and conceivably go into Ford's smallest cars, like that Fiesta shown above.

The tiny 1-liter engine is being designed at a Ford technical center in the United Kingdom. The goal is to create an engine that gets the same or better miles-per-gallon as a 1.6-liter four-cylinder engine. Ford isn't saying how many miles a gallon such a miserly powerplant could develop, but it already has some 40-mile-per-gallon models for the highway, and 50 mpg on the highway doesn't seem out of the realm of possibility.

The last time we remember three-cylinder engines being sold in the U.S. was on some Suzuki Swifts and a sister version from General Motors, the Chevrolet Metro, in the '90s. They got such astounding mileage ratings that even beaters were selling for top dollar when gas prices hit all-time highs in 2008.

"Consumers are telling us they want to buy affordable vehicles that get many more miles per gallon," said Derrick Kuzak, global product development chief. "Our new 1-liter EcoBoost engine will give consumers looking for hybrid-like fuel economy a new, more affordable choice."

He describes the new engine as "a little dynamo." Features of the new engine include:

An offset crankshaft that helps improve fuel economy.

An advanced, Ford-designed split cooling system that allows the cylinder block to warm up before the cylinder head. Faster cylinder block warm-ups save fuel, especially in cold weather.

An exhaust manifold cast into the cylinder head. The one-piece assembly lowers the temperature of the exhaust gases. This enables the engine to run in a wider rpm band with the optimum fuel-to-air ratio. The new design also saves weight and allows the engine to operate more smoothly.

EcoBoost technologies, such as turbocharging, direct injection and twin independent variable camshaft timing.

First seen in the Ford Start concept car that appeared at Beijing in 2010, the engine more recently made its European debut in the Ford B-MAX at the 2011 Geneva Motor Show. More details will be released in September at the Frankfurt Motor Show in Germany.