• Nov 30th 2009 at 3:58PM
  • 47
When oil prices shot over $100 a barrel a year ago, I was inundated with press releases from inventors claiming they had an engine that would solve the energy crisis. In most cases, I simply deleted each release and went on with my work. You see, I've seen this all before.
The same thing happened after the oil shocks of the 1970s. All kinds of inventors came up with all kinds of engine designs, promising to solve the country's energy problem. But not one of those engines ever made it into production.

In most cases these new designs only existed on paper. In other cases, the efforts were led by people who had no clue what it takes to break into the automotive industry. Think about it. In the last 100 years only three engines have made it into mass production: the gasoline engine, the diesel engine, and the rotary. And only Mazda has stuck with the rotary.

But recently I got to see a new type of engine that makes me think it might have a chance. Part of that has to do with the design of the engine. The other part has to do with who is behind the project.


John McElroy is host of the TV program "Autoline Detroit" and daily web video "Autoline Daily". Every week he brings his unique insights as an auto industry insider to Autoblog readers.
Eco Motors is the name of a new company that has come up with a radically new type of engine. It has two opposing pistons in two contiguous cylinders, connected to a common crankshaft in the middle of the engine. An electric supercharger provides boost on demand. It's a two-stroke engine with no valves, yet still achieves 90% scavenging efficiency with less oil consumption than a four-stroke engine. In other words, it's a two-stroke engine that can meet the strictest emissions standards. It can be made as a spark-ignited or compression-ignition engine, and the diesel version can meet emission standards without using urea.

Believe me, my description does not do this engine justice. Click on the accompanying videos to get a better understanding of how this works.


Eco Motors calls this the OPOC engine, which stands for opposed piston, opposed cylinder. The most intriguing part is that it's a design which is half the size and uses half the parts of a conventional piston engine. Eco claims it can be built for 20% lower cost and 30% lower investment than traditional internal combustion engines (ICE's). And it claims it can provide a 15% improvement in fuel economy.

But Eco also says that by pairing two of these engines together you can get a 50% improvement in fuel economy. In this arrangement, one engine shuts off in light throttle applications, then instantly fires up for full throttle acceleration. This would boost fuel economy 50% over a conventional ICE, since there are no pumping loses when the second engine shuts down.


So, for example, instead of building one 150-hp OPOC engine for a compact car, you'd build two 75-hp OPOC engines and connect them together. Even though this dual-engine arrangement would erase the advantage of having fewer parts, it would still result in an engine that's half the height of a current ICE. Eco Motors showed me engineering schematics where a dual-engine layout would easily fit in the engine compartment of any of today's compact front-wheel-drive cars.

What makes Eco Motors worth paying attention to is that this engine is more than just a design study, or a CAD simulation. Eco invited me over to Roush Industries to watch one of their working prototypes running on a dynamometer, where it's already racked up over 500 hours of test time.

Just as importantly, the OPOC engine was designed by Peter Hofbauer, who spent 20 years at Volkswagen designing diesel engines and the VR6, that narrow 15-degree engine. The CEO is Don Runkle who was the chief technology officer at Delphi and played key roles in the original Corvette ZR-1, Buick Racing and the Chevrolet Indy effort. The COO is John Coletti who used to run the SVT engineering operations at Ford. In other words, these are people with a proven track record who know how to get things done in the auto industry.

Sure, it may turn out that this is just another one of those engines that ends up on the ash heap of automotive industry. But of all the alternatives I've seen so far, this one intrigues me the most.


Autoline Detroit
Airs every Sunday at 10:30AM on Detroit Public Television.

Autoline Detroit Podcast
Click here to subscribe in iTunes

Follow Autoline on Twitter for ongoing updates every day!

I'm reporting this comment as:

Reported comments and users are reviewed by Autoblog staff 24 hours a day, seven days a week to determine whether they violate Community Guideline. Accounts are penalized for Community Guidelines violations and serious or repeated violations can lead to account termination.

    • 1 Second Ago
      • 5 Years Ago
      have a look to http://www.astremo.com
      we believe in BEV + REX
      we develop opposed piston engine to REX no vibratio and 2stroke
      we develope air (Oxygen) activation
      and we like TOM a unike IVT from TEXAS

      We have 400 engines on display in the museum
      doing research since 20 years
      have a look to http://books.sae.org/book-r-378

      • 5 Years Ago
      "radically new type of engine" ?!! JUMO (Junkers Motors) made similar kinda two stroke diesels during WW2.
        • 5 Years Ago

        used on the Dornier Do 26 flying boat.

        "These engines all used a two-stroke cycle with six cylinders and twelve pistons, in an opposed piston configuration with two crankshafts, one at the bottom of the cylinder block and the other at the top, geared together."
      • 5 Years Ago
      Unlike some wonky ideas (that spinning radial piston thing from the last Duesenberg concept comes to mind) , at least the basic opposed-piston concept has been around in working form for over a century. That long outer conrod has historically been an issue with OP design (that's why most have 2 cranks), so it'll be interesting to see how this turns out.
      • 5 Years Ago
      There are many viable alternative ICE designs. The best one I saw was the radial cylinder engines of the MYT engine (google it). Yet most if not all of them seem to disappear.

      And most people by now know why. The weight of the establishment in industry and government is so heavy we have ended up with a monopolized system where the industry picks and chooses what technologies it wants to use, and the criteria have nothing to do with user satisfaction or technological viability. We don't have a free market, we have crook capitalism.

      This is why we're not using ethanol. This is why the electric car, by far the best overall technological option, is such an uphill struggle. This is why 30 000 more young victims are going to be thrown into the grinder in Afghanistan.

      Because it's all lies and manipulations. Were we, the people, able to make our own technological choices (and I admit it is our fault we don't), we would quickly see this current energy scarcity economy fall to bits, as people choose and implement better technology than technology the marketing dept currently lies to us as being the best.

      And many automotive journalists, on establishment payrolls, have been actors on this stage. Popular Mechanics, for example, lies through it's teeth regarding 911, lord knows what it makes up about engines...

      This current engine design is intriguing, another one for the bookmark, thanks. Although it's no frictionless electric motor of course.

      My 5c.
        • 5 Years Ago
        I'm not too concerned, the FED has already obliterated the dollar anyway...
        • 5 Years Ago
        It's true. It's so difficult for an upstart engineer or inventor to actually get an idea off the ground (and protect his/her idea), thousands of brilliant and possibly industry-shifting ideas get thrown by the wayside.
        • 5 Years Ago
        Tin foil hats go!

        Really though, automotive companies don't have the money to invest in every single technology that comes along. They are trying to make money (which is difficult now). It costs a lot to even just develop a new piston ICE let alone develop something completely from scratch that may not end up working.
      • 5 Years Ago
      100 MPG seems to be a pipe dream right now.
      • 5 Years Ago
      I can't imagine any of the big companies using this engine anytime soon, if ever, but I can definitely see a company such as Fisker using it. Instead of the largish 4-cylinder charging the battery, stick this engine in. Half the size and less weight, lower center of gravity.
      • 5 Years Ago
      Honestly, and I hate to sound like a consipiracist(sp?) but automakers could have brought out a 100mpg car decades ago, and could tomorrow, if it was profitable to the right people. The point is, the right people aren't making enough money off of efficient cars, and until it becomes highly profitable we will see crappy mediocrity like this hybrid nonsense. I realize it's a stepping stone, but build me a car with this motor and I'd gladly choose it (assuming it's proven durable) over a gas/electric hybrid like a Prius. Why are we being shuffled into one option for efficient driving?
      • 5 Years Ago
      That engine design has been around for more than 100 years. There is a car from the early 190x's in the Nethercutt collection (Sylmar, CA) that has that exact same configuration. It's a 1909 Gobron-Brille (http://nethercuttcollection.org/Cars.aspx?era=antique).

      It's like deja-vu all over again, I posted the exact same comment on a previous thread about this engine: http://www.autoblog.com/2009/08/02/ecomotors-opposed-piston-opposed-cylinder-engine-ups-power-den/

        • 5 Years Ago
        True that. The claims the company makes are totally bogus, and just the language they use is sickening.
        • 5 Years Ago
        This isn't quite the same; scanning that link, it seems like the Gobron-Brillie is a four stroke cycle (it speaks of inlet and exhaust valves,) the OPOC is a two-stroke with blower scavenging.
        • 5 Years Ago
        From the old thread about this engine:

        "Here's a link to a diagram of the 1909 Gobron-Brillie engine:


        Look familiar? Nothing like digging up designs from the past and claiming them as your innovation...."
        • 5 Years Ago
        As John R. Bond, the late, longtime publisher of Road & Track, used to say, "There's nothing new under the sun gear".
      • 5 Years Ago
      It does get tiring to hear people cry how everything is a conspiracy. For instance, everyone likes to talk about "breakthroughs" but rarely, super rarely, is there anything close to a quantum leap in technology. It's always small improvments over time where eventually someone looks back at the first model and says "wow, this is WAY better now than then!" But it still took time.

      It's like saying we should somehow be able to magically go from the model-T to a flying car that runs on a thimble of sweat a year.

      Seriously, Zeph, the US is a VERY free country, and if you really think someone like Bill Gates couldn't fund an electric car that would blow away a gas powered one IF HE WANTED TO but that he doesn't because of some crazy conspiracy, you should re-think your level of paranoia. He can't do it because it's un-economical to, and technically impossible.

      There is no shortcut from here to there. Just chill out and accept it.

      • 5 Years Ago
      It is, of course, pointless to argue against a conspiracy theorist; the very lack of evidence for the conspiracies is seen as evidence for them!

      That being said, for the record.

      1. There is no evidence that Tesla ever built a car that was powered through beamed power in the 1920s and 30s. Just a story that has grown more and more elaborate in the retelling. It would be possible, today, to build such a car, but hardly practical to replace 100 million cars with them (since the infrastructure needed to beam power to them all would be gigantic).

      2. Ethanol is not practical.. particularly not when using corn. Brazil can do it using Sugar Cane, but Brazil is also wrecking their environment. The future of bio-fuels (if any) requires us to develop fuels that will not require us to take land out of food production. The fact that Ethanol is even considered in this country is because of the farm lobby in Washington.

      3. Until you can build an electric car that recharges in 5 minutes and can go 250+ miles on a charge... or rebuild all American roads to essentially power the cars directly (like subway tracks), electric cars are not going to be able to completely replace cars powered with ICE.
        • 5 Years Ago
        But what about using a hydrocarbon extracted from an organic oil? Or perhaps vaporizing it before running it through the engine? Or the fact that a diesel wasn't invented to even run on petroleum products? Interesting conspiracy theory ain't it! Basic fact, but doesn't exist. Right?!?!?! Tinfoil black helicopter rawwwwr.
      • 5 Years Ago
      The difference with this engine is that at least the concept 1) works, and 2) is a proven configuration. The opposed piston two-stroke has a long history in large diesels; one of the more notable designs was the Napier Deltic used for stationary and large marine applications.

      There was also the Rootes-Lister opposed piston two-stroke diesel which was used in on-road/off-road trucks decades ago; but like most two-stroke diesels, it fell out of favor when four stroke engines proved easier to clean up w.r.t. emissions.

      The big "gotcha" I see with this OPOC engine is high moving mass.
      • 5 Years Ago
      This is pretty cool.
      Would be interesting to see the working prototype.
      Maybe you could take it for a spin and a long drive Top Gear style to test its fuel efficiency.
    • Load More Comments
    Share This Photo X