autoboy is quite right here. The last thing you want is a small displacement car with a high ratio overdrive gearing, giving you very low RPM at highway speeds. This will cause the transmission to "hunt" (look constantly for a lower gear, then rev up, then drop into overdrive, then downshift, then rev up, on and on) and it will drive you crazy, trust me.
A high-torque engine (torque is related to cylinder displacement but not the # of cylinders necessarily) can handle a higher ratio OD, such as say a 3.5 liter V6 or a 4.0 and up V8.
Some automakers, in the quest to advertise higher MPG, have made this compromise, making their cars very annoying drive on the highway. Fortunately, VW knows better apparently.