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Opposed Pistons & Other Pressing Automotive Issues

#AchatesPower #engineer #Chrysler


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Do you remember the Junkers Jumo 205 engine? Unless you’re an aircraft aficionado or familiar with San Diego-based Achates Power, probably not, because the heyday of the Junkers Jumo 205, a two-stroke diesel engine used for aircraft, was in the 1930s.


According to David Johnson, president and CEO of Achates Power, back in 2004 some people started thinking about the potential of opposed-piston, two-stroke diesel engines, and figured that they could take the highly efficient basic design used way back when in Germany and provide contemporary technology to it and consequently achieve an engine that would better the fuel efficiency of even a state-of-the-art automotive diesel by 20%.

And so that’s what Achates has been doing. One cylinder. Two opposed pistons moving toward each other on the compression stroke. Moving back on combustion. An engine, Johnson says, is simpler and less expensive to manufacture (no valves; no cylinder head), yet can be manufactured with existing production equipment (a tooling change is necessary, of course, but unlike, say, manufacturing motors for a hybrid vehicle, it is pretty much straight forward).

He’s not talking about one cylinder engines, but a six cylinder engine would be a three, an eight a four.

The whys and whats and hows of this technology is what Johnson talks to John McElroy of “Autoline,” Peter DeLorenzo of Autoextremist, and Gary Vasilash of, well, this, on the latest episode of “Autoline After Hours.”

And as is the case always on the program, there is a lively discussion of various topical items—ranging from management changes at Chrysler and Nissan to the collaborative efforts on transmissions by Ford and GM—prior to the guest coming on the show.

You can see it all here:

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