In the new 2011 Chevrolet Cruze, GM is without any fear downsizing its four cylinder engines, and looking for turbocharging to bring small-four fuel economy without sacrificing peppiness and drivability in most of the Cruze lineup.

And a naturally aspirated, 1.8-liter four-cylinder engine will be standard on the base Cruze LS, the fuel-efficient star of the lineup—and the engine on offer in all the rest of the Cruze trims—is a new (to North America) 1.4-liter turbocharged four-cylinder engine that produces 138 horsepower.

According to GM, the engine, which will also be installed sans turbo in the 2011 Chevrolet Volt, will offer best-in-segment fuel-efficiency (40 mpg highway in the Cruze Eco), and calls it “one of the most fuel efficient four-cylinder engines of its kind in the world”

But it’s worth noting a few key design differences between the Cruze and the all-new 2012 Ford Focus that’s waiting in the wings, for introduction just a few months after the Cruze.

Ford is planning to offer a larger standard engine on the Focus—a 2.0-liter unit—featuring direct injection for one. And it will be the only engine on offer at launch, but a version of the automaker’s EcoBoost turbocharged four-cylinder engine—likely a 1.6-liter—is also expected to follow.

The engine produces its 148 lb-ft peak torque at just 1850 rpm, and as reported with a preview drive of the 2011 Chevrolet Cruze on companion site The Car Connection, the Ecotec 1.4T really does feel like a larger-displacement four—more like a 2.2-liter in overall responsiveness.

As for why GM didn’t opt to install direct injection in the U.S. version of the 1.4T, it was a conscious decision to hold down cost and complexity for the Cruze, a vehicle for which price will be very important.