6 stroke engine

Discussion in 'Hybrid' started by boat fan, Oct 3, 2011.

  1. boat fan
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    boat fan Senior Member

  2. hoytedow
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    hoytedow Bananas

    There was almost a 7th stroke when I saw that!
     
  3. Petros
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    Petros Senior Member

    It is not exactly clear how this engine works but it appears he is using one piston to compress the air for the combustion chamber in the adjoining cylinder. The power piston works on a two stroke principle in order to get one power stroke per rev. I do not see how this can be more efficient, almost all of the two stroke driven vehicles have gone away in favor of the more efficient (even if heavier for the same hp) four stroke engines.

    He has not explained how this is more efficient in terms of fuel in vs. power out, nor that it will have lower emissions.

    There have been variations of similar concepts around for a long time, like 100 years. He has an up hill battle if he thinks he can invent something at home that is better than some what some of the world's largest corporation, with the best engineers and big budgets have developed. Some of the idiotic government requirements on cars and engines also prevent really efficient cars as well.
     
  4. Elmo
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    Elmo Junior Member

    Yes I thought that too .The "piston charger" seems to act like a valve ?
     
  5. Manie B
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    Manie B Senior Member

    On this video is a diagramatic explanation
    dont worry about the language
    the drawings explain well - midway in the video simulation

    http://www.youtube.com/user/6stroker#p/a/u/2/a2WNa9MX5qU

    sorry nothing new
    these "inventions" have been around for donkey years
    every now and then a new one pops up

    JUST ANOTHER TWO STROKE with a different twist
    dont hold your breath, you wont see this one ever either
     
  6. kerosene
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    kerosene Senior Member

    its seems that this was invented in the VHS era...
     
  7. Fanie
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    Fanie Fanie

    Petros, the four stroke motors suck. Have a look at the low pressure injection two stroke motors, better in every way. For marine apps two stroke will always be my motor of choice.
     
  8. Petros
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    Petros Senior Member

    why do u say 4-stroke sucks? They have been developed to a highly refined state, modern 4 strokes are very reliable, clean and efficient. Yes they have more parts, and are larger and heavier for the same amount of hp, but I have not found the two strokes I have owned to be better at all. I have found the 2-strokes to be very finicky, always needing tweaking and adjustments, etc. Frankly I think they are obsolete for anything but very simple engines like chainsaws or string trimmers (and even than they are still a lot of work to keep running all the time).
     
  9. Fanie
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    Fanie Fanie

    Good grief no ! Two strokes run forever, have lots more torque than a four stroke, are lighter in weight end requires nothing other than changing spark plugs once in a blue moon. The only drawback they had they were dirty and emmissions was high. This however was changed with the low pressure injection on two strokes. making them clean and more fuel efficient while retaining the superior torque.

    You need only to follow the complaints on the internet of the 4 stroke motors performance to realize there is a bit of a problem. Any size two stroke performs much better than a same size four stroke simply because it has a lot more grunt.

    There are a few comparrison video's on youtube the two-strokers will be glad to show you :D
     
  10. Petros
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    Petros Senior Member

    I get in my 25 year old car and it always starts, runs many 1000s of miles without even checking it, takes lots of abuse, and I continue to expect it to run for many 1000s more miles. I have chain saws and string trimmer than seize up after only a few 100 hourse of use, I change the spark plug and have to adjust the carb every 10 to 20 hours use, they never idle worth a darn (I have to keep my hand on the throttle to keep it running).

    So I do not know what two strokes you have experience with, but all of my experience has not been good. Granted I have only had small engine two stroke experience, but none of it has been good. BTW, all of the ultralight aircraft have slowly switched early on from two stroke over to four. Yes, the two stroke is very powerful for its size, have fewer parts and are much simpler, they have a big advantage there. But I suspect there is little incentive to modernize the two stroke because of emissions regulations, so they all are effectively obsolete and out dated compared to modern 4 stroke engines large and small.
     
  11. boat fan
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    boat fan Senior Member

    Yes , would have to agree with that Petros.

    Diesel even better , at least for boats.
     
  12. PAR
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    PAR Yacht Designer/Builder

    The two stroke, four debate has raged for years and from a technical stand point it's been over for years, yet some still cling to hope for the 2 stroke. Direct injection, swirl valves, pre-combustion chambers, etc. all have been tried, but with modern controls, a 2 stroke doesn't have a chance against a 4 in gas. In diesel, it fairs better, but still suffers from the same issues.

    About the 6 stroke engine above. It reminds me of the old "sleeve" engines that were played with in the early 20th century. Half of the reciprocating mass is preforming no work, so the engine is essentially doomed. A 5 liter foot print (size and weight) engine assembly with the output of 2.5. Now there's an idea. His "re-compression" stroke appears to me nothing more then a renamed exhaust stroke and I suspect it'll have a huge heat build up issue, with all that free riding reciprocating mass.

    But what do I know . . .
     
  13. boat fan
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    boat fan Senior Member

    Yes , I was thinking that also , but was not confident enough to say so.
     
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  14. Fanie
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    Fanie Fanie

    Things change.

    I was always a petrol motor in a car fan, even though diesel was an option many still preferred petrol. This kinda forced the diesel okes to come right and if you compare the performance of these new diesels I would prefer the new diesels as well. Lots of torque low down in the revs - ideal for towing and still being very economical.

    Same happened to two stroke, when 4 strokes were brought out all the eager beavers went for 4 stroke for the lower fuel and cleaner running. You know the crowd that always had to have the newer-better-than-every-one-else.

    This forced the 2 strokers to redesign and they did it. Have a look at the low pressure fuel injection motors, Evenrude makes them and Tohatsu makes them too. Not far behind on fuel consumption, clean burning and with a lot more torque than the four stroke and lighter in weight.

    Yep, a lot of guys that had ie 60 hp 2-strokes on the boats replaced them with 60 4-strokes and were disappointed not getting the boat on the plane - had to up to the next size motor then experience weight problems. There's a place for everything, and I cannot say the 4-strokes fitted in yet.

    What can I say, I'll still take the 2 stroke every time...
     

  15. Squidly-Diddly
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    Squidly-Diddly Senior Member

    Here is one l like Wobble or Swash plate engine.

    http://en.wikipedia.org/wiki/Swashplate_engine

    Doesn't mention it here, but some guy at Audi? had made an engine like this, with the added feature that the angle of the plate, and the position of the plate on the shaft could change during running.

    So both the compression ratio(s) and displacement could be modulated while the motor was running. I say "ratios" because obviously changing displacement would itself change compression ratios.

    The idea being you could drop displacement and compression for idling, and increase both for hard running, etc. Also adapt for wide range of fuel, without compromising the "hard specs" of a normal engine's piston sweep. Variable timed valves can only do so much.
     
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