Ford Authority

Super-Efficient Opposed-Piston Engine To Start Testing In A Ford F-150

Achates Power and Aramco Services have developed a new, super-efficient gasoline internal-combustion engine that will start testing in the Ford F-150 later this year. The 2.7-liter mill features an opposed-piston design, with six pistons and three cylinders; uses a two-stroke cycle; and features zero spark plugs, relying instead on compression ignition.

Achates and Aramco are far from the only companies taking a novel approach to trying to squeeze every last bit of efficiency out of the internal-combustion engine. Nissan’s Infiniti brand is close to┬álaunching a turbocharged variable-compression engine that can dynamically alter its compression ratio during operation, and Mazda’s forthcoming Skyactiv-X gasoline engine is chasing greater efficiency by using a supercharger and its own clever method of compression-ignition.

Like both of those, the Achates Power/Aramco Services opposed-piston engine utilizes forced induction, in the form of both a turbocharger and a supercharger. Here, they’ll help control engine response in place of varying valve lift and timing, as there are no intake or exhaust valves.

The opposed-piston engine itself is nothing new; various examples started appearing toward the end of the 19th century, and notably, James Atkinson used an opposed-piston design for his first Atkinson Cycle engine. Over the years, opposed-piston engines have been used tanks, trucks, locomotives, and airplanes.

When the twin-charged, two-stroke opposed-piston engine of Achates Power and Aramco Services tests in the Ford F-150 later this year, the companies are hoping to see around 33 mpg – or about 37 mpg by CAFE standards. That’s because, where the typical modern internal-combustion engine can achieve somewhere around 25% thermal efficiency, Achates/Aramco say that their design can achieve about 45%.

For context, the refreshed, 2018 Ford F-150 4×2 is rated at 22 mpg combined when fitted with the 2.7L EcoBoost V6.

Testing with the Achates/Aramco-powered Ford F-150 should begin in late-2018, at which point we’ll find out whether the two companies’ efficiency forecasts are correct. If they are, the opposed-piston engine could prove an efficient, viable alternative to some of the more common engine designs.

(Hat-tip: Roadshow)

Aaron Brzozowski is a writer and motoring enthusiast from Detroit with an affinity for '80s German steel. He is not active on the Twitter these days, but you may send him a courier pigeon.

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  1. Hans Oqvist

    Interested of vevcles with motor in CGI material.

  2. Lee

    Two stroke? Heavens to murgatroid! Wait till the greenies get wind of this.
    Sounds like something designed by Volkswagen and BMW.


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