Car Tech 101: The Atkinson Cycle engine explained (On Cars)
The Atkinson Cycle engine may be under your car’s hood and you’d never know. Brian Cooley discusses the technology and why it’s becoming a mainstay in late model, efficient cars.

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27 thoughts on “Car Tech 101: The Atkinson Cycle engine explained (On Cars)

  • October 6, 2015 at 3:02 pm

    Why push air back out, why not just let less in to start with?

  • October 7, 2015 at 1:11 am

    this comment is meant for youtube/google.

    does a video less them 2 minutes rally need a advertisement????? i mean really?????

  • October 7, 2015 at 10:07 am

    looking at old tech is fun. thank you Tesla 🙂

  • March 4, 2016 at 5:54 am

    How does leaving the valve open not just dump out fuel

  • April 30, 2016 at 11:48 pm

    Its the "wonky linkages" that make an Atkinson engine what it is. The linkages allow for the complete cycle to be completed in 1 crankshaft revolution. That's what makes an Atkinson engine unique.

  • September 14, 2016 at 1:45 pm

    This is also known as a Miller Cycle by Mazda. Essentially the difference is Miller Cycle engines are supercharged and leaving the intake valve open longer gives more time to charge extra air and fuel into the cyclinder.

  • March 12, 2017 at 5:59 am

    With variable valve timing and turbos this engine seems incredibly stupid. An engine that sacrifices low end torque is useless for everyday driving.

  • March 13, 2017 at 7:10 pm

    Sooo you're saying the Atkinson is the low flow toilet of engine cycles?!

  • June 9, 2017 at 4:43 am

    So would an Atkinson cycle engine with direct injection lead to heavy carbon buildup since some of the air/fuel mixture would kind of be pushed back into the intake manifold and there is nothing to clean off the back of the valves?

  • June 11, 2017 at 11:17 pm

    Doesn't pushing out some of the fuel air mix just eject unburned fuel along with the air?

  • June 16, 2017 at 3:46 am

    this si some modified atkinson cycle, the original atkinson has a short compression and a long explosion in order to extract more power from the small air fuel charge

  • July 24, 2017 at 5:24 pm

    1:35 Wonky? It looks genius. People were expert engineers back then. Their math skills were way above.

  • August 16, 2017 at 3:59 am

    You do NOT understand how this works and messed up the explanation.

  • October 3, 2017 at 2:51 am

    Or you could just tune the stupid engines correctly to begin with. It's always either underpowered, too heavy, too lean, too rich, poor timing, or poor flow of gasses. Getting the rigjt balance does NOT equal 500hp, but it does mean better power to weight and a thorough (and clean) burn. That means far less time on the throttle.

  • March 1, 2018 at 7:30 pm

    Atkinson's most successful design was a 2 stroke called the Utilite' . He made that version in 1893. it had the same feature of a short compression stroke and a longer expansion stroke but it used a conventional rod and crank.

  • March 26, 2018 at 2:07 am

    it's a horrible idea and would have alarmed Atkinson

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