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

  1. #436
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    Quote Originally Posted by hightower99

    I am still betting another friend (hopelessly in love with your idea )
    100DK that you will be all but forgotten in less than 5 years.

    Do you personally believe that the revetec design is that much better than the normal crank designs out there. Do you think you can beat over 100 years of refinement?
    I've been around for 11 years in development already and have met our goals and are going forward in leaps and bounds so what more can I say.....5 years forgotten?......Yeah right....We plan to be in production by the end of the year.

    Not only do I know our design is alot better but so do 1,500 investors that are supporting us putting their money where their mouth is, and several automotive companies, our federal government and OS military entities.

    So are you saying that a school student knows more than several large automotive companies? Please answer this question because I want everone to either see you admit you don't know it, or, say that you know more than companies with over 2,000 engineering staff and a $6 Billion turnover.

  2. #437
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    Quote Originally Posted by revetec
    So are you saying that a school student knows more than several large automotive companies? Please answer this question because I want everone to either see you admit you don't know it, or, say that you know more than companies with over 2,000 engineering staff and a $6 Billion turnover.
    In another thread hightower99 was telling us he knew more about engine design than BMW's engine design genius, Paul Roche.

    To know more than those 2,000 engineers will be no challenge at all for him.
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  3. #438
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    Quote Originally Posted by nota
    I watched the Channel 7 Financial News broadcast last Sunday with considerable interest as they did a glowing feature on the Revetec engine. Included were Brad and the eager trike-manufacturer client (previously poster on UCP) who spoke openly in keen terms about obtaining 5000 units iirc to power his product

    Brad - any chance of posting this on the site? It looks like the Seven website have archived the Sunday news bulletin.

    Guys can we please stop these personal attacks. The last few pages have been quite boring and are taking away from a great thread. Hightower, I have known Brad for about ten years. Before the company became a public company, Brad was more than happy to openly discuss the engine. But since the company took the next step to become a publicly listed company, it is like getting blood out of a stone when it comes to confidential and sensitive details.....as it should be. You have some valid questions but patience is the key here. The details will come out in time. OK he explained why they didn't come out around Christmas and these delays happen. If you were trying to get a deal that would set your company up for the future, why would you jeapodise that in a public forum. So if you have no further new questions, let's not go around in circles. The previous questions from yourself, pneumatic and others are documented and I am sure they will be answered when Brad feels he is breaching no laws or confidentiality agreements.

    I am one of those 1500 shareholders that Brad mentioned and I have an extreme amount of faith in the engine and REVETEC staff.

  4. #439
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    Quote Originally Posted by CHOOK
    Brad - any chance of posting this on the site? It looks like the Seven website have archived the Sunday news bulletin.

    Guys can we please stop these personal attacks. The last few pages have been quite boring and are taking away from a great thread. Hightower, I have known Brad for about ten years. Before the company became a public company, Brad was more than happy to openly discuss the engine. But since the company took the next step to become a publicly listed company, it is like getting blood out of a stone when it comes to confidential and sensitive details.....as it should be. You have some valid questions but patience is the key here. The details will come out in time. OK he explained why they didn't come out around Christmas and these delays happen. If you were trying to get a deal that would set your company up for the future, why would you jeapodise that in a public forum. So if you have no further new questions, let's not go around in circles. The previous questions from yourself, pneumatic and others are documented and I am sure they will be answered when Brad feels he is breaching no laws or confidentiality agreements.

    I am one of those 1500 shareholders that Brad mentioned and I have an extreme amount of faith in the engine and REVETEC staff.
    Well stated, here, here

  5. #440
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    Quote Originally Posted by hightower99
    I am still betting another friend (hopelessly in love with your idea )
    100DK that you will be all but forgotten in less than 5 years.
    It's not going to happen. This is not high school, it is the real world.

    Quote Originally Posted by hightower99
    Do you personally believe that the revetec design is that much better than the normal crank designs out there. Do you think you can beat over 100 years of refinement?
    Yes.

  6. #441
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    Quote Originally Posted by revetec
    I've been around for 11 years in development already and have met our goals and are going forward in leaps and bounds so what more can I say.....5 years forgotten?......Yeah right....We plan to be in production by the end of the year.
    I hope so cause I have been waiting for awhile (the bet started as a 7 year bet)

    Quote Originally Posted by revetec
    Not only do I know our design is alot better but so do 1,500 investors that are supporting us putting their money where their mouth is, and several automotive companies, our federal government and OS military entities.
    Well if you and several automotive companies ect. Know that this design is better than it is only because you have all the information.

    Quote Originally Posted by revetec
    So are you saying that a school student knows more than several large automotive companies? Please answer this question because I want everone to either see you admit you don't know it, or, say that you know more than companies with over 2,000 engineering staff and a $6 Billion turnover.
    Did I say I know more?
    I said you haven't convinced me due to complete lack of evidence. Obviously I am a critical person and I am not going to jump on the band wagon just because you say it is better and because a few 3rd world maybe 2nd world auto manufacturers have decided to give you a chance. I also can't know more than others who have seen your evidence (that you say you have). Really if it turns out that you make the important stuff public (or I get my hands on one) and that the evidence is clear and valid then hey I will not be as critical about the revetec design. Until then I still see problems.
    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.

  7. #442
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    Strictly Technical, Balancing X4:

    “Thanks for your comments but we have been developing this engine for 10 years and we have laid out the engine that way for a reason. 1st: as I before mentioned the output shaft would not be able to deal with the torque if it was the balance shaft. 2nd: being a development engine, the balance shaft is located at the top for ease of changing the balancing when modifications are made.”

    The 1st is wrong: When a shaft of 70mm diameter is eccentrically cut to create the one 1st order counterbalancing weight of the X4, the resulting shaft is more strong than a 50mm diameter shaft, which is by far more strong and inflexible than what is necessary to pass half of the total inertia and combustion torque of the X4.
    Even in case Revetec needs counterbalancing shafts of more than 70mm diameter, the “intermediate” synchronizing gears between the two shafts can be of larger diameter than the one third of the big spur gears: each balancing shaft has two spur gears, the primary one is meshed to its mate big spur gear at a 3:1 ratio, the secondary one is meshed to an equal secondary spur gear secured to the other balancing shaft. The secondary spur gears can have diameter larger than the 1/3 of the big spur gears and still the output shaft to rotate once per piston reciprocation.

    The 2nd is true if Revetec thinks it is preferable to load the engine with additional bearings, shafts and spur gears only to “change the balancing when modifications are made”. I was wrong to think I had heard everything.

    It’s up to Revetec to use additional balancing shafts. But the justification is not convincing.




    Strictly Technical, the thrust loads:
    ”The thrust loads on the bearings are deflected into the opposing cam. If you modelled our assembly and a conventional engine and you performed an analysis on the assemblies you will find that 36% of a conventional engine's load transfers to downward force on the crank, and our assembly only has 11% downward force on the shaft (the balance is converted to rotational forces by the opposing cams.”

    The thrust loads: Based on their animations, the X4 Revetec arrangement, compared to the Boxer Revetec arrangement, has the two rollers of a piston in a significantly longer distance. This means significantly increased thrust loads. These two rollers push the two tri-lobe cams. If the two tri-lobe cams were on the same plain, the thrust loads would be zero. But as the two tri-lobe cams are in a significant offset from each other, the reaction of the cams to the rollers create a significant pair of forces that tends to rotate the piston about the cylinder axis. If you leave the piston free into the cylinder, it will rotate. To keep it from not rotating, a wall is necessary to provide an opposite pair of forces. This is the thrust load. This is what has to be compared to the thrust loads of the conventional. With a con-rod to stroke ratio of 2:1 in a conventional, the thrust load to the vertical load is 25% at 90 deg after TDC and only 12.5% at 30 deg after TDC. What is this ratio in case of X4 at 90/3 deg and at 30/3 of the tri-lobe cam?



    Strictly Technical, Revetec rev limit:

    ”Our engine failed in India due to a damaged cambelt spocket in transit. This intern caused the cambelt to fail at which time the valves hit the pistons at 4,600rpm. Due to the huge momentum mass of the diesel dyno, the output flange shaft cracked when the engine stopped suddenly. The valve stems were in a "S" shape but there was no damage to any other components, such as cams bearings etc. Which proves the strength and reliability of our internals. This failure had nothing to do with our technology either so your comments are just blowing in the wind. Our engine performs well upto 6,000rpm currently and our new engine has a safety factor of 4.5 at 6,000rpm. That means it is 350% over engineered.”

    After the failure of the Boxer Revetec engine in India / Mahindra on September 2006, and according Revetec’s Directors Announcement: “it is expected that the further testing will take place the next 3 – 4 months” (3 to 4 months sounds too long if the basic mechanism of the engine was unaffected).

    It is now more than 4 months.
    Did the tests of the Boxer Revetec completed, or the whole “Boxer Revetec” project is “phased out” (canceled) for the sake of the X4 arrangement?

    And if someone had to sent from Australia to India ten people with a single engine to test, or five people with an engine to test and a “back up” engine “in case …” , or twenty people without any engine at all, I think the “back up” engine “selection” is the reasonable one.




    Strictly Technical “the long connecting rod”.

    “Yes, the higher the conrod ratio, the higher reving the engine. Standard car about 1.55:1, EVO 1.65:1, F1 engine about 2:1 and so on. I have performed tests with a sine wave cam and it does not perform or breathe at lower RPMs.
    If you were to put some decent breathing on the Patakon engine you will find that it will continue to perform better at even higher RPM's. But remember that the higher the RPMs the more fuel you are using to achieve the output. “

    The fact that Revetec failed to make a “long connecting rod” engine to breath efficiently at low and medium revs is completely different than to accept as a physical law that a “long” connecting rod conventional cannot breath efficiently at low and medium revs”.
    Pattakon’s 354 cc single cylinder Harmonic engine (it is like a conventional with a connecting rod to stroke ratio not only 2:1 -like F1-, not only 10:1, not only 100:1 but infinite) provides on the flywheel more than 3 Kp*m of torque at 3.000 rpm, with only one intake and only one exhaust valve. This, according Revetec, is called “inefficient breathing”!
    Is it necessary anything more to prove that Revetec’s theory for the long connecting rod is wrong?
    Revetec’s “law” that relates the breathing efficiency of an engine to the connecting rod length is as wrong as it gets. The plot on which this Revetec “law” was based, proved – beyond any doubt - mistaken on previous posts.
    Formula 1 engines use very long con rod to stroke ratios (2:1 or more) because it is impossible for them to use shorter: the two pistons (100mm diameter with 40mm stroke) hit to each other if short connecting rods are used.
    It is a strictly geometrical subject, it is also a strictly simple subject.


    In my previous post I was wondering whether there is a car with a Revetec’s engine on it for tests. From Revetec’s reply, it seems there is not. It seems that “all the money” (hopes) are now on the X4 airplane model.
    I am the last to blame Revetec for trying. They try.
    But it is not a good sign when Revetec’s posts are full of “high school level” mistakes.


    I wish to be true that Revetec X4 is designed with a 4.5 safety factor at 6000 rpm (whatever Revetec means by this). After all this would be great for the future of Pattakon’s GRECO. But . . .



    Strictly Reality:

    “If you want to pedal your engine Manolis, start a topic on it! Don't be scared.

    I've seen the video of your engine spiting and spluttering, oh yeah...and the one of a tacho. Where is one we can see an engine in a vehicle driving or running on a dyno. I'd like to see it for my own interests. Can you email me a video please?

    Thank you for your comments Manolis, I have enjoyed reading them.”


    I think Revetec will enjoy better driving than reading.

    For the video A1.MOV at http://www.pattakon.com/vvar/OnBoard/A1.MOV (the one with the tacho of the Honda Civic), it seems Revetec doubts for its authenticity.

    So:
    The car is on a public road with the driver and a passenger.
    With the first gear it goes to 9000 rpm where the rev limiter is set.
    With the second the same.
    At 7500 rpm with third the gas pedal is released because the car was dangerously approaching other cars going slower.

    Does Revetec think this video is too good to be true?

    If yes, Revetec has an invitation to come in Athens to make a video himself, any time. In case Revetec will see less than what the video shows, his airplane tickets and 1st class Hotel in Athens will be paid by Pattakon.

    But instead of Revetec, Pattakon prefers Mahindras’ R&D director to come in Athens and drive the cars himself. Tickets and Hotel prepaid by Pattakon.

    Or even better both, Mahindra and Revetec are welcome.

    If Revetec or Mahindra have a representative (or a friend) in Athens, he can also confirm that the cars and the engines exist, and that 9000 rpm is nothing special, any place any time.


    Thanks
    Manolis Pattakos

  8. #443
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    Dear Manolis:

    1stly is is advantageous to have the output shaft inline with the centre of the engine. Having a propeller or flywheel offset is not suitable for most applications, so your idea wont work, so stop going on about it.

    About thrust loads....you constantly missing the point and I'm getting tiresome of your statements. I'm talking about deflected thrust from converting reciprocating motion into rotational motion. Go back and read previous threads. I posted a diagram.

    Conrod ratios....Ho hum....This has been discussed before. Many companies have tried to run a sine wave piston plot. The most prominent is the scotch yoke engine....Guess what?....It's supercharged.....Why? Because with a sine wave plot the initial piston velocity is slow and has poor volumetric efficiency.
    You state that your Pattakon engine goes to 9,000rpm...?????????? Why so high in a production car? 9,000rpm is getting closer to better breathing efficiency. 9,000rpm means more fuel usage. You go on and on about it, why don't you post an analysis of volumetric efficiency of a normal conrod ratio and an infite on like your family's engine, and post the analysis. Make it and indepenent report from a reputable entity please. High revs doesn't mean efficiency.

    So how about posting third party testing results compared with the standard car. Power torque and fuel consumption....better still BMEP figures.

    My thinking is the only reason your posting here and being pissed off with this discussion is to pedal your families engine. Don't you think it's strange no one has started a topic on your engine?

  9. #444
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    Manolis, I think you need to grow up and be an ENGINEER about this and stop being childish.

    As suggested earlier, you shoudl create a thread and describe the advantages of the engine you clearly support. Then you can justify it on it's own merits without trying to throw mud and obfuscation. ( or do you not wish a repeat of hte refutals at Atlas ? You touted this idea way back in '03 and took some stick on it last year iirc )
    Last edited by Matra et Alpine; 02-01-2007 at 03:35 PM.
    "A woman without curves is like a road without bends, you might get to your destination quicker but the ride is boring as hell'

  10. #445
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    Quote Originally Posted by hightower99
    the wankel engine in the RX-8 would be classified as a 3.9L engine.
    Quote from the RX8main forum: The RX-8 has a rotary (Wankel) engine with a capacity of only 1300cc. There are two rotors in tandem, each with a capacity of 640cc according to Mazda. But the DVLA in the UK rate it as 2.6 litres, as do most insurance companies. This is because a Wankel engine can generate one power impulse per central shaft rotation: a normal (Otto cycle) piston engine generates one-half of a power impulse per cylinder per crankshaft rotation. You'll note that the SCCA (Sports Car Club of America) defines engine capacity as the sum of the swept capacity (i.e. max cc - min cc) of the cylinders for a conventional engine, but twice that capacity for a rotary engine. This is why.

  11. #446
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    OK guys. You wanted it. Here it is.

    Here is the link to the new Pattakon thread.

    http://www.ultimatecarpage.com/forum...ad.php?t=31037

    Can we now keep this thread to technical aspects of the REVETEC engine and the other for the Pattakon.

    Cheers

  12. #447
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    Good one Chook! Can you start another one for Hightower99 called...Ummmmm...
    Engineering for school kids, or
    Hightower99's 3.9 litre RX8, or even
    Genius Hightower....smarter than BMW's Paul Roche.

    Hehehehe! You gotta see the funny side of that?
    Last edited by revetec; 02-01-2007 at 08:39 PM.

  13. #448
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    Quote Originally Posted by revetec
    Quote from the RX8main forum: The RX-8 has a rotary (Wankel) engine with a capacity of only 1300cc. There are two rotors in tandem, each with a capacity of 640cc according to Mazda. But the DVLA in the UK rate it as 2.6 litres, as do most insurance companies. This is because a Wankel engine can generate one power impulse per central shaft rotation: a normal (Otto cycle) piston engine generates one-half of a power impulse per cylinder per crankshaft rotation. You'll note that the SCCA (Sports Car Club of America) defines engine capacity as the sum of the swept capacity (i.e. max cc - min cc) of the cylinders for a conventional engine, but twice that capacity for a rotary engine. This is why.
    And you call me stupid?

    This just proves your lacking intelligence...

    First you quote a forum that is not official and has a reputation for making assumptions and quoting things wrong (much like you do)

    First lets get some facts straight.
    Quoted from Official Mazda Online Brochure for RX-8
    Each rotor has a swept displacement of 654cc (so not 640cc like you said)
    Total displacement is therefore 1308cc for static displacement.

    The wankel is classed as a two stroke system by some organisations solely because it produces 1 power pulse per output shaft rotation per rotor. To be a real 2 stroke engine it should achieve both exhaust and intake during the same stroke (i.e. as the rotor face closes in on the rotor housing). This is not the case and is therefore not a true 2 stroke, the wankel engine follows a otto cycle (i.e. 1 stroke per operation: intake, compression, power, exhaust). Displacement of a whole engine is defined as the volume displaced by each unit (piston or rotor) during the course of a single otto cycle. By this definition the engine displaces 1.3L however you could consider each face of the 3 sided rotor as a single unit. If you did that then the engine displaces 3924cc (3.9L). Simple really. Now you realise that the wankel engine is either a 1.3L 4 stroke that can achieve 1 power pulse per output shaft revolution per rotor(2 rotor RX-8 engine has 2 pulses per output shaft revolution), or it is a 3.9L 4 stroke that fires 1 rotor face per output shaft revolution (basically thinking of it like a 6 cylinder engine that produces a total of 2 power pulses (that overlap a good deal) per output shaft revolution). Lastly others have decided that it wasn't fair to call it either so they classed it as a 2.6L 2 stroke engine that produces 1 power pulse per rotor per output shaft revolution.

    I hope you can understand this now.
    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.

  14. #449
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    http://www.mazda.com.au/rx8/specifications.aspx?ID=43http://www.mazda.com.au/rx8/specifications.aspx?ID=43

    From Mazda themselves.......1,308cc not 3.9 litre

    You think you know but you don't!

  15. #450
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    Hey Hightower99, Why don't you get mazda to agree with ya and post it here?

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