BMW's N20 engine--four cylinders, more power

More power, greater torque, reduced fuel consumption, lower tailpipe emissions and less weight--but better? Before driving the BMW X1 xDrive28i, the first model to feature the German carmaker's new turbocharged 2.0-liter four-cylinder gasoline engine, we weren't so sure.The new engine, known as the N20 and set to lead a return of four-cylinder BMW models to North America for the first time since