Ward’s 10 Best Engines competition has recognized outstanding powertrain development for 20 years. This installment of the 2014 Behind the 10 Best Engines series highlights development of Ford’s 1.0L 3-cyl. EcoBoost.

As we know, an inline 6-cyl. engine is inherently balanced, one good reason why the typical BMW I-6 feels so silky smooth.

But it also is physically long, making it a tough fit in transverse front-wheel-drive applications even in large and midsize cars (though Volvo found a way with its lovely, but outgoing, 3.0L I-6), let alone in smaller cars.

That is why all other automakers still offering 6-cyl. power have moved to more compact and easier-to-package V-6s.

But a bank of three cylinders is inherently unbalanced, and mating two banks of three into a V-6 (depending on the angle between them) does little to help the problem.

V-6s typically use counter-rotating balance shafts to offset that unbalance, so imagine a 3-cyl. without balance shafts: Rough as a road full of potholes after a long, hard winter.

Yet now, given fast-accelerating U.S. corporate average fuel economy (and European carbon-dioxide emissions) requirements, automakers increasingly are turning to new compact, lightweight I-3s as more fuel-efficient alternatives to I-4s in small cars.

And given their inherent harshness, these new triples (as some call them), definitely need balance shafts to make them livable.

Or do they? Ford's 1.0L I-3 team had a better idea.

"A 3-cyl. has a natural first-order imbalance that is normally counteracted by a balance shaft," says Steve Gill, Ford's engine chief engineer.

"But that adds cost, weight and friction, which hurts efficiency. So we came up with the solution of putting imbalance on the flywheel and the front pulley and moving the imbalance plane from primarily vertical to primarily lateral, which can be accommodated in the engine mounts. That gives great refinement without the cost, weight and fuel-economy downsides of a balance shaft."

While adding flywheel and pulley weights doesn't completely eliminate a triple's first-order couple, changing that motion from vertical to horizontal makes it easier to counteract.

An I-3's natural vertical pitching and hop can be difficult to isolate, but the horizontal motion mostly can be absorbed by specially designed engine mounts.

Gill says balance shafts are intentionally heavy and driven by a system that requires lubrication, so doing without them also reduces the engine's lubrication complexity, and that, to his knowledge, is an industry first.