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

  1. #346
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    Quote Originally Posted by pneumatic
    The book is 100's of pages, it has a ridiculous amount of research and work put into it. There's a lot more air cooled engines in the world than just the VW engine you know.

    If you want a source that you can't pick holes in, then look at the Bosch Automotive Handbook, a well known resource in the industry. It too agrees with the 1/3 rule (but expands the ranges to 30-35%).

    Look, I think the X4 looks really interesting. I am not denying that. It looks smaller and lighter, but by how much is yet to be seen. And your X4 is a radial engine, so to get a better idea of size you really need to compare it with the complexity and size of a radial conventional engine;

    I think Shane's comments are great, and his opinion is encouraging for the success of your motor. But it still does nothing to prove your efficiency claim. That is after all, what I have been asking for more information on all along.
    I have proven to all parties I have presented to that the thermal calculation is wrong. I have proven it in actual tests. I know it is hard to accept. When I first started presenting to a panel at QUT they thought I was mad. After the presentation they sent me a letter that stated that I could increase thermal efficiency of this engine to over 50%.

    I thought it was opvious that a guy who has a patent on a heat exchanger would claim such high thermal losses. He is incorrect. At the time of writing his book it was probably accepted in the industry as being correct. Today a better knowledge of engines is known. I see it time and time again, people quoting from old information. The Universities and Tafe colleges still quote 100 year old theories. It has been taught for so long it must be right? It does relate to a certain extent to conventional engines but not all engines. For example: A rotary engine has far more thermal loss that a conventional engine but is has better mechanical efficiency because it doesn't have to stop/start a piston. So late model rotary engines are getting reasonable efficiencies these days. What would it do if the thermal losses could be brought in line with a conventional engine?

    Our engine is no more radial than a V8 or VR6 engine. I don't mind you calling our X4 version a radial but it's not really a radial as such. Any engine acually has the cylinders radially from the crank.

    As far as Shanes comments, The engine is injecting around half the fuel of a comparable engine and he has driven the trike on many occasions. He has told you how it feels to drive. My feelings is I would describe it like a steam train. Acceleration is almost consistant from a standing start to max revs. It feels very unusual and has an almost regular turbo boost feel to it, but it performs better down low.

  2. #347
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    Quote Originally Posted by jediali
    so have I - where have you been?, good to have you back- and on form. I agree with most of your points here. On the feeling torque agenda - is an engines responsiveness anything to do with instantaneus torque? In my car i know the engine is struggling when i lose the ability to swiftly increase the engine speed with the throttle, suggesting no more pulling ability left.

    Since power comes from 1)displacement 2)torque 3)engine speed more low down power is technically more torque. Also, objectively speaking, a flat torque curve would suggest a linear power curve, hence linear acceleration (at low speeds, before exponential wind resistance effects de-linearise the system) can be observed. Compare this with a peaky NA engine or a HP turbo engine where torque comes in surges the acceleration also hapens in surges. The differences may be very subtle...just a thought mate
    I suose as a rough idea, Torque is the pulling power you feel. Power is then how fast it accelerates. If you are driving up a big hill and your car slows down, you put your foot down and it pulls up the hill strongly but the revs dont increase, you are feeling the effects of torque. If you shift down and then accelerate up the hill, then power is being displayed.

    That is right. You will feel constant acceleration from low to high revs with no peaks. This provides the best driveability for most people. Some people like the peaky feel. Flat torque also provides good economy due to the fact you don't have to rev the engine high to get the power going into effect.

  3. #348
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    Quote Originally Posted by jediali
    theres always a simple solution.........
    This engine is like a convention engine though. The features and characteristics I'm bringing into engines cannot be achieved with an crank engine. Remember that our engine can be a boxer, X, V and inline engine.

  4. #349
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    Quote Originally Posted by hightower99
    Ok if the Lambda says you are running 14.7:1 air/fuel ratio then that is for the whole cylinder... if it isn't then the system has a serious flaw. If you where running 14.7:1 air/fuel ratio during both 2000 and 4000rpm then you needed to inject MORE FUEL when you where running at 4000rpm. That is just simple math. You need to explain where your advantage is?


    I think you might have misunderstood what he said I would bet money that he said something closer to "I don't care about Peak Power... the torque curve is more important" this would be an intelligent and true statement. To believe that he said he wasn't interested in the power curve at all is ridiculous. Again I believe that even when he said torque is important he meant low rpm power and the shape of the power curve as this determines the driveablity of the engine. I talked to a engineer from japan and he said he knew that torque was more important than peak power... He took me driving in two civics he had been working on. One was pretty much stock 2001 civic with 1.7L I4 and 5 speed manual. It had 111lbs-ft. of torque and 117hp. The other one he had put a small tubo on that boosted peak torque to 201lbs-ft. but power was only increased to 130hp. He then did some hard accelerating with me in the passenger seat and showed me some dyno charts. The turboed Civic did pull really hard compared to the stock one even though the peak hp was only 130hp (only 13hp more than stock). The interesting thing was the dyno charts that showed 30-45hp increase over stock between 2000 and 6000rpm.
    When we compress the lean mixture into a smaller area and ignite it the same amount of oxygen is consumed giving a consistant lambda reading.

    A good example is a high compression engine. The higher the compression the more power and efficiency. The only problem is detonation so higher octane fuels are used. You have probably noticed that some fuel companied are promoting better fuel that it more dense. This is too allow an equivalent of a richer mixture at the plug for firing but reduces knocking so more power is produced on a leaner mixture. A leaner mixture provides better efficiency due to hotter combustion temps. A richer mixture is easier to fire. Normally a lean mixture under load will misfire. Toyota has a new engine with two injectors. One in the head for richer mixture at the plug and one in the port for overall lean mixture.

  5. #350
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    Quote Originally Posted by hightower99
    Yes more torque is needed at low rpm to create more low rpm power. My point is that you feel the power. The power is what moves you.
    Sorry, you have that the wrong way around. It's torque that moves you and power is torque X RPM. Don't take my word for it, talk to a Uni or any techical development person from any engine manufacturer.

    Cheers

  6. #351
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    Quote Originally Posted by Matra et Alpine
    never such a thing as "simple" solution to complex problems.
    Radials have major vibration issues and the combustion vibration being the most difficult to counter

    btw TORQUE gets you moving, power keeps it.
    And they produce a gyroscopic effect which is not good for aviation as it makes the plane harder to turn.

  7. #352
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    Quote Originally Posted by jediali
    there was a hint of sarcasim in my reply there! Yep torque moves you, power gets you there quickly.

    Hey Matra do you know the (main) difference between the 189 and 228 bhp rx-8 engine? i will tell you - the intake port is longer on the lesser power version - which produces more torque (because a steady heavier mass of intake air ensures better cylinder filling and hence better mean effective pressure which is essentially torque). Consider the rotary with a variable intake, that would give you the best of both worlds. awesome
    Good comment: A longer intake does provide good torque. This is why they make variable length intakes. Short gives you a more responsive engine and long gives good midrange torque.

  8. #353
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    Quote Originally Posted by hightower99
    the high power model has a 3 stage variable length intake system... and of interest is the fact that one of the intake tracts that opens on the highpower version is longer than the others... and this extra intake tract isn't on the lower power version...

    Torque doesn't move you and to prove it I ask a simple question...

    How much torque does an engine need to make to accelerate to 60km/h in 10 seconds while hauling 3000kg in a trailer...

    I can tell you roughly how much power it is gonna take...

    Bet you can't tell me how much torque....
    Get a V8 and a high performance 4 cylinder both with the same power to pull a 3 tonne trailer. Which one does it easier. Can a 750hp Formulae 1 car pull a 3 tonne trailer off the mark? They have trouble getting themselves off the mark (10,000+ rpm and dumping the clutch to get wheelspin is the only way. Remember most of your driving is stop/start.

  9. #354
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    Quote Originally Posted by hightower99
    Torque in itself doesn't move anything... You need to have the time componant to do anything therefore power is what moves you.

    I would point out that your example is missing so pretty vital information. Where am I exerting the torque? in relation to what? If I exerted this torque on the car's CoG nothing would happen in either case.

    My question was to figure out how much torque the engine needs to generate to move the vehicle you can't tell me this... therefore engine torque (not Physical Torque in a general sense) is pretty irrelevant.

    Consider that gearboxes don't effect power (it doesn't matter what gear you are in the same power is always available).
    And you cannot produce power without torque.

  10. #355
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    Quote Originally Posted by pneumatic
    I think the Torque vs Power discussion should be taken to a different thread. It is subjective and will go on forever.

    Brad,

    Just fill in the blanks below so we know what your saying with regards to economy.

    At 2000rpm the engine uses ____L/min of fuel to make _____HP.

    At 4000rpm the engine uses ____L/min of fuel to make _____HP.

    From what your saying, the L/min will be the same for each, and the HP is double at 4000rpm.
    On a conventional engine yes. From our engine NO. If we did the engine would not perform and show it running rich. You can say all you like. Ring Peter from Haltech. He has programed our engine. Or maybe Wayne Jones who programs many of the V8 SuperCars. They both will tell you what I am saying is true. We actually don't program our engines ourselves. Way back when we were using Motec engine management, Wayne Jones came in as a consultant and programed our first engine. Wayne then consulted to Haltech when we swapped ECUs. He stated to Peter when he arrived at Revetec "Forget everything you know about programing an engine, this engine needs a totally different fuel and spark map"

    Look I can't prove it to you unless you see it on our Dyno running. I think this year we will be doing the rounds of motorshows around the world with this engine, so look out for us and check our website in the future about where and when we will be.

  11. #356
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    Gotto do some work now.

    BTW: I do have alot of work to do now so I'll be a bit less active on this forum for the next month.

    Cheers and thanks for your discussions, it has been good chatting to you guys.

  12. #357
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    Quote Originally Posted by revetec
    Look I can't prove it to you unless you see it on our Dyno running.
    I'll assume that the fact you can't produce such simple fuel consumption figures means that you haven't actually had this tested and therefore do not have figures to quote.

    And;

    Quote Originally Posted by revetec
    After the presentation they (QUT) sent me a letter that stated that I could increase thermal efficiency of this engine to over 50%.
    Can you post a scan of that letter, I am sure there is no confidentiality problem with doing so. I went to QUT myself.

  13. #358
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    Quote Originally Posted by pneumatic
    I'll assume that the fact you can't produce such simple fuel consumption figures means that you haven't actually had this tested and therefore do not have figures to quote.

    And;



    Can you post a scan of that letter, I am sure there is no confidentiality problem with doing so. I went to QUT myself.
    Pneumatic: I can tell you know nothing about larger businesses or how QUT actually works with reports.

    I can show you at an open day where it is publically available to everyone.

    The independent fuel usage figures have been produced with Mahindra. We are still under agreement with them and I'm not going to breach that to show you.

    I can't show you documents that are deemed confidential and I cannot disclose information to a select few without announcing it on the NSX or ASIC website due to the fact it affects our share price.

    I can show you a letter from QUT but in doing so I will have to pay QUT for the usage. I will pay a few grand to show an important client but not to post on here. This is how the UNI makes money. Free report then pay to show the results.

    If you get a 1999 version of out prospectus, it think it is in thatfrom memory, I don't have a copy to check.

    The thing is that many of you don't know how difficult it is to release information when you are on the stock exchange. You must disclose contracts and information that is relevant, but you can't release confidential information that could lead you to being sued. Yeah sure I'll show you and not have a job tomorrow and lose everything........Jeeeeesh.

    We are a public company on the National Sock Exchange, We have over 1,500 shareholders, we have a $1 million federal government grant, we are working with an US$ multi billion turnover automotive company. If all I had was smoke and mirrors, I wouldn't be at this stage buddy.

    Cheers
    Last edited by revetec; 01-17-2007 at 09:55 PM.

  14. #359
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    Quote Originally Posted by pneumatic
    I'll assume that the fact you can't produce such simple fuel consumption figures means that you haven't actually had this tested and therefore do not have figures to quote.

    And;
    Can you post a scan of that letter, I am sure there is no confidentiality problem with doing so. I went to QUT myself.

    Mate, I think you and a few other here are missing the point. Brad will provide the data (which is confidential data) to this forum when he is good and ready. I am sure if you or any of the other forum members had an interesting piece of innovative technology that you would not be sharing data etc that could compromise a deal or allow a competitor to have an unfair advantage.

    He has received a federal government grant based on data that he has shared with them and not you ( $1 million).

    He has received intererst from Mahindra and other manufacturers based on data that he has shared with them and not you.

    Perhaps they know something that you and I don't??

    We should be thanking him for contibuting what he has to date; if this technology does become the next big thing then you have all been documented on this forum as being opposed to it. Now, lets give Brad the benefit of the doubt, let him complete building the engine, let him finish producing the engine test results and then you can go to town on him.

    Until then it is a pointless exercise arguing this further.

    The engine looks great, it is commpact in size and appears to have the basic foundation to be used across various applications.

    Great ideas get shot down all the time. This is an idea that can actually contribute towards saving our environment. It is about fuel economy whilst not having to compromise on power or torque. Lets wait till Feb/March to see if he has delivered.

  15. #360
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    I know how large companies work, I work for one of the worlds largest engineering consultancies.

    The data I am asking for isn't exactly going to give your design away. So it looks like we are back where we were on page 10, there is nothing to discuss until you release some testing figures. Back then you said you were going to release the info at xmas, but I guess there have been delays. It is probably the delay detailed below, which explains that you probably don't have the test data at this stage;
    Quote Originally Posted by revetec announcement 6 October 2006
    During testing we observed that the data showing one of the critical key aspects of the
    Revetec Technology, namely the flat torque curve was consistent with the flat torque curve
    characteristic obtained from Revetec’s own testing result. Also noted a further important
    characteristic aspect namely that our engine at full throttle used the approximately the same
    amount of fuel at 4,000 rpm as it did at 2,000rpm which was very exciting.

    Before the performance of the engine on its full range was concluded, one of the cam belts
    failed due to a damaged tooth on the pulley which may have happened during transport and
    was not visible on start up. This occurred at 4,500rpm which resulted in the valves hitting the
    pistons at high speed and inturn damaged the output shaft. The testing could not continue
    and hence complete data could not be captured.
    One minute the article from QUT is a letter, the next it is a report that you have to pay to show people, yet you put it in the prospectus. So you say it is in the 1999 version of the prospectus, hmmm, that is strange, because in 2002 you said (reference - http://autospeed.drive.com.au/cms/article.html?&A=1500);

    "The first thing I did was go to Queensland Institute of Technology. I'd come up with the concept but I wanted someone else to verify what I was doing. I presented (the idea) to them and, first off, I said that I was going to increase the level of thermodynamic efficiency beyond 50 percent. They laughed at me. They laughed, so I said 'well, I'll prove it to you.'"

    I believe that they are still waiting for you to prove it to them, and so are we...
    Last edited by pneumatic; 01-17-2007 at 11:06 PM.

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