I've noticed that engines have gotten very complicated, thus more complicated in the past few years in to squeeze more power and efficiency out of them, Ford's ecoboost in particular. I was wondering if it would be just as efficient to equip FWD cars with a small, very undersquare inline sixes instead of inline four engines of equal lengh? For example, could you build an inline 6 with a bore of 2" and a stroke of 4" instead of a 4 banger with a bore of 3-3.5" and a stroke of 4"? Would the extra low-end torque give the engine better efficiency or would any gains be canceled out by the extra "surface area" (cylinder side-wall area?). Would such an engine have such poor aspiration that it would need a turbo to be compareable in power in to an inline 4 of similar displacement?