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Thread: A work of pure genius! - Brilliant "Revetec" Engine

  1. #466
    Join Date
    May 2003
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    99
    Revetec’s Law of Aspiration

    “Any engine with connecting rod to stroke ratio more than 1.7 cannot breath efficiently. The only way is the supercharging.”

    A good evidence, according Revetec, is the use of con-rod to stroke ratio more 2.0 and more in Formula 1 where the typical rev range is between 10.000 to 20.000 rpm.

    Pattakon has built a single cylinder Harmonic engine (look at www.pattakon.com web site) that provides in the flywheel more than 3 Kp*m of torque at only 3000 rpm, with only two valves, from 354 cc (75 Bore, 80 stroke). 15 years ago.
    But who cares, and who believes, what Pattakon made, measured and say?

    I previously used another way to prove to Revetec that their “Aspiration Law” is nothing but nonsense.
    When two 100mm Bore pistons reciprocating in a 40 mm Stroke share the same crankpin (V8 and V10 Formula 1 engines), any con-rod to stroke ratio less than 2.0 make them hit to each other. Is it so difficult? If you still confused I can make an animation to show you the case.

    In case of Newton’s law “Force=mass*acceleration”, law means that we didn’t find in our world an exception. No matter a black of a white man measures the mass, the force and the resulting acceleration, no matter when he measures them, no matter where the measurement takes place, no matter … the law is always true. Otherwise it is not a law.

    Similarly for the Revetec’s “Law of Aspiration”, if it is a real law and not nonsense, it must be true for every engine, anywhere, anytime.
    So either Pattakon lies claiming a naturally aspirating engine with excellent breathing and con-rod to stroke ratio not just over 1.7, not just over 2.0, not just over 1000 but infinite (this is what harmonic engine means: its piston performs the motion of the piston of the conventional with con-rod to stroke ratio infinite) or ...

    Except Pattakon, others built pure sinusoidal (harmonic) engines too ( i.e. infinite con-rod to stroke ratio).
    One of them is the Australian CMC.
    Unless what they wrote in their web site is not true, they designed and built a whole series of naturally aspirating engines, they made “long” tests in many of them, they even sold a few of them to car makers for tests etc.



    They write for their kinematic mechanism, they write for less vibrations, for more compact design, for lower consumption, for better combustion and fewer emissions due to the longer dwell of the pistons at TDC etc etc.
    And every one of their engines does use natural aspiration. Doesn’t it?

    These are “clumsy” mistakes. Aren’t they?

    It is a fact that Revetec failed to tune properly their sinusoidal engine.
    It is also a fact that others made sinusoidal engines with excellent aspiration at low – medium revs without any need of supercharging.
    So, it seems the genius needs some more courses on engine aspiration.

    An engine with a Pattakon VVA on it, would help.

    Thanks
    Manolis Pattakos

  2. #467
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    May 2003
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    99
    Regarding the Pulling Rod Engine







    To achieve the long piston dwell near combustion, they shatter the unity of the crankshaft and use the “synchronizing” gears to connect the two crankshaft halves at the two sides of the cylinder ! ! !

    So, using two connecting rods per piston, a long piston pin, two crankshaft halves and a “gearbox” between the two crankshaft halves, they finally achieve what the Pulling Rod Engine does.

    It seems they know:
    nothing about breathing,
    nothing about friction,
    nothing about production cost,
    nothing about combustion,
    nothing about engines.

    But you know what?
    The above drawings are from a patent granted to Honda, on September 2004 (four years after the patent for the Pulling Piston Engine was granted to Pattakon).

    Thanks
    Manolis Pattakos
    Last edited by manolis; 02-05-2007 at 10:42 PM.

  3. #468
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    CMC Power systems went into liquidation in 2004.

    ASIC Report

    Why? Because they failed to prove the product and sign up with an interested party. Mechanically the design is simple and seems good. So what went wrong Manolis?

  4. #469
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    Manolis: Look at this link explaining about the cons of a longer conrod ratio

    The effects of con rod ratios

    Quote from the above website:

    Effects of a long rod

    Con:
    They do not promote good cylinder filling (volumetric efficiency) at low to moderate engine speeds due to reduced air flow velocity.

  5. #470
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    May 2003
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    CMC’s design seems simple but is not adequate.

    They have thrust loads on the piston skirts: as long as the crankpin is at an angle (piston not at TDC), the double piston is supported by the square bearing at an offset from the cylinder axis. This forces the double piston to rotate around the crankpin center (imagine the piston at the middle of the stroke). The only way is the two ends of the double piston to touch the cylinders and create an opposite pair of forces to keep the double piston from not rotating.

    These thrust loads are small compared to the “thrust” loads between the “square” bearing and the relevant surface made on the double piston “body” that interconnects the two pistons.
    The loading of this “square” bearing is similar to the loading of the piston skirt of the conventional engine with the difference that the conventional has only a small portion of the total inertia and combustion forces to pass through the piston skirt to the cylinder wall, while the CMC design passes the total load (inertia and combustion) through the double piston body to the square bearing.

    This seems the reason for their failure.
    This, after all, was their “difference” to the other sinusoidal designs.
    The Bourke’s engine was actually a CMC without the square bearing.

    On the other hand, let suppose their failure came from their incapability to make their engine breath efficiently at medium and low revs, as Revetec insists.
    The problem with incapability of breathing is apparent not at partial loads but in WOT operation.
    The plot of their WOT torque and power says this is not the case.



    The plot shows that CMC’s engine breaths efficiently from 1000 to 5500 rpm.

    From another viewpoint, if the breathing was the problem and the supercharging was a solution, what stopped CMC from supercharging their engines? The problem was elsewhere.


    If I had to explain why Bourke’s engine failed, I would say its kinematic mechanism could not stand the “punishment” of the roller bearing loading for long (endurance limit).
    If I had to explain why CMC’s engine failed, I would say their kinematic mechanism creates, at specific conditions of revs and loads, too much friction. And the improved combustion of CMC may compensate for the increased friction, but the wear is unavoidable.

    PS: As for the drill, it wasn’t just a hummer drill, worse even it was a destroyed one with a “play” of the drill nose of some millimeters.

    Thanks
    Manolis Pattakos

  6. #471
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    Manolis: You are only defending your long con rod theory because it effects your families product.

    Why are street cars using a conrod ratio of around 1.6:1 and F1 use 2:1?

    If it didn't make a difference then street cars would use 2:1 or higher to reduce piston side loadings and increase reliability and efficiency. F1 would go higher than they are, because with such a short stroke a small change to the conrod length would increase the ratio dramatically.

    So why do street cars use around 1.6:1, higher performance cars use 1.7:1, F1 use 2:1? Can you see a pattern there?

    So what are the performance changes using a pull rod engine using an opposite ratio or the Greco using a infinite ratio?

    Looking at the pattern of used ratios, I assume that it will be a very high revving engine. What do you assume?
    Last edited by revetec; 02-06-2007 at 12:36 AM.

  7. #472
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    We know that stroker engines are higher performance and produce higher power at higher revs. This adds reciprocating mass and you would expect most looking for a high performance engine to try and increase the bore and keep the stroke short which would be most peoples thoughts looking for high revs. But a stroked crank requires a longer conrod. So why does it breathe better at higher RPM and produce higher power with this modification. You would assume a longer stroke would benifit at lower revs with higher torque. But stroker engines rev higher (Such as drag cars pulling hard over 8,000rpm).

    Anyway we can debate this forever. I know performance engines use a higher conrod ratio. I have tested short, long and infinite ratios in our engines and know the effects, so whatever you want to say to defend your families designs, I know you haven't tested the effect yourself so you can only go on about theory and graphs which is not used in the production motoring industry.
    Last edited by revetec; 02-06-2007 at 12:42 AM.

  8. #473
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    By the way Manolis, do you know that you can modify any engine's heads, intakes, exhausts, camshafts etc to increase breathing. So giving graphs and data from any one specific engine that has not changed conrod ratios doesn't prove anything. One would have to only change a conrod length to determine performance changes (As they do in performance and race cars, which they raise the ratio anywhere up to 2.1:1, being F1).

    As far as the CMC 1.4 litre engine....90-115Nm of torque isn't exceptional. We were beating that by 25Nm 2-3 years ago with our previous 1.35 litre engine.
    Last edited by revetec; 02-06-2007 at 12:53 AM.

  9. #474
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    Quote Originally Posted by manolis
    Revetec’s Law of Aspiration

    “Any engine with connecting rod to stroke ratio more than 1.7 cannot breath efficiently. The only way is the supercharging.”
    Your quote is wrong. I said it is a higher revving engine. An infinite conrod ratio will breathe better at very high rpms.

  10. #475
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    Jan 2007
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    I am one of those 1500 shareholders that Brad mentioned and I have an extreme amount of faith in the engine and REVETEC staff.
    I too am a shareholder. One of the early ones (I think) when the engine was just a humble garage built prototype.

    I have that much faith I have already picked out my new red Ferrari (well almost)

    Hi Brad, do you know who this is? clue....Are you still going to hold me to running naked across the harbour Bridge when I make my first Million?

    I'm almost there now so this will be icing on the cake and a potential early retirement fund.

    Stop reading this post and get back to work and make me money on my investment!

  11. #476
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    Brad, I read this article on ninemsn tonight.

    The European Commission will propose carmakers should be required to reduce carbon dioxide emissions from new cars to an average of 130 grams per kilometre by 2012, a European Union source said on Monday.

    The Commission would target an overall cut in car emissions to 120 grams per km by 2012 from current levels of roughly 161 grams per km, but that goal would be achieved through biofuel use and other technology in addition to improved standards from carmakers themselves, the source said.
    Have you got any figures on the emissions of the current design? I remember at a REVETEC open day a few years ago where you had a previous engine running that you could put your nose right next to the exhaust and could hardly smell any exhaust.

    Thanks

  12. #477
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    Quote Originally Posted by RVC Shareholder
    Stop reading this post and get back to work and make me money on my investment!
    Exellent
    Love the power of shareholders

    Brad, nobody here ( well except one ) will think anything if you just ignore the posts baiting you to justify yourself and promote other products.

    I concur, get back to work and get more results to come tell us info as often as possible and answer questions that you can and only have to once !!!
    "A woman without curves is like a road without bends, you might get to your destination quicker but the ride is boring as hell'

  13. #478
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    Quote Originally Posted by Matra et Alpine
    I concur, get back to work and get more results to come tell us info as often as possible and answer questions that you can and only have to once !!!
    Yeah 16 hours a day isn't good enough. There are 8 wasted hours you could use.

  14. #479
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    Quote Originally Posted by CHOOK
    Have you got any figures on the emissions of the current design? I remember at a REVETEC open day a few years ago where you had a previous engine running that you could put your nose right next to the exhaust and could hardly smell any exhaust.
    Too bad you can't smell CO2...
    Power, whether measured as HP, PS, or KW is what accelerates cars and gets it up to top speed. Power also determines how far you take a wall when you hit it
    Engine torque is an illusion.

  15. #480
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    Quote Originally Posted by hightower99
    Too bad you can't smell CO2...
    Guess what? You couldn't smell too much burning fuel either

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