Ilmor Engineering Shows Off 5-Stroke Engine Concept

Ilmor Engineering 5-stroke engine

Ilmor Engineering 5-stroke engine

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With the automotive world striving for smaller, more efficient engines in a bid to be seen as environmentally-conscious and attract customers, scientists and engineers are coming out of the woodwork with new combustion engines, electric powertrains and other systems that they tout as the future of automotive technology - just this month we already saw EcoMotors' opposed-piston opposed-cylinders project that promised to revolutionize engine design.

Now, an engineering firm by the name of Ilmor has announced its own new redesign of the internal-combustion engine, with claims that efficiency gains of between 5% and 20% can be had. What makes us actually sit up and take notice of Ilmor's claims is the company's history, having built Formula 1-winning engines for Mercedes-Benz and working with a number of Indy car teams for over a decade to build engines - not exactly amateurs, then.

The new, more efficient engine Ilmor is proposing promises to deliver the fuel economy that current diesel engines can achieve, without the associated emissions problems the oil-burners typically offer. Designed for road cars, rather than its usual work with racing applications, the Ilmor-designed 5-stroke gasoline engine is a diminutive 700cc three-cylinder unit that still manages to develop 130 horsepower and 122 pound-feet of torque.

According to Ilmor, the 5-stroke concept engine utilizes two high-pressure fired cylinders operating on a conventional 4-stroke cycle that alternately exhaust into a central low-pressure expansion cylinder, whereupon the burnt gases perform further work. The low-pressure cylinder decouples the expansion and compression processes and enables the optimum expansion ratio to be selected independently of the compression ratio.

The end result is that the engine runs an overall expansion ratio approaching that of a diesel engine – in the region of 14.5:1. The engine is also more compact, and unlike other new technologies does not require any new manufacturing techniques. The engine is just a concept for now, with further development expected to take place. Eventually, the company hopes to achieve a power density figure of 150 horsepower per liter of displacement.
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Comments (9)
  1. seems to me at 120hp for 700cc, theyve already gotten 150hp/L

    another interesting idea....... that will never be adopted. the OEMs would rather work with forced induction.. an advanced ad sophisticated technology, but one that is proven. Ilmor will have to prove the engine tech with a smaller firm before anyone else will even bother looking. its the same song and dance.

  2. It's true, these technologies seem to pup up here and there, but you never see them actually reach production. Shame.

  3. In this concept little some parts...

  4. It's like turbocompounding without the turbine

  5. wonderfull engine..

  6. Not new.1906 Compound USA had same system.3 cylinder rated horsepower 16.

  7. how much minimum no. of cyl r required for this sys.
    Pls tell me

  8. This is the sort of new engine technology that is going to keep the automotive industry on the rise. New technologies need time, often a lot of time (10-15 years) to reach production. Keep the new engine technologies coming.

  9. to Ivan.. can i get the source as a proof that the 1906 Compound is using this system? I mean a diagram or specifications. Just for my study materials.. Thanks...

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