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#61
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VWs
wrote:
But try to hot rod it and you may (or may not) live to regret it. For what it's worth... YMMV Richard Thanks, Richard, for sharing all those insights and experiences. Robert Padget's 1/2 VW parasol: http://www.youtube.com/watch?v=eps0zQP2SeE Paul Hammond's 1600 VW parasol: http://www.youtube.com/watch?v=vSxM-BrXnd0 takeoff: http://www.youtube.com/watch?v=se0fRqMUoUc landing http://www.youtube.com/watch?v=v-jrHDvyJ4c The trials and tribulations of a new motor (VW)... http://www.youtube.com/watch?v=ckjqfUM5xlw |
#63
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VWs
A collaboration of half a dozen guys. * * (open source?) I drew up the plans and wrote the manual. Argh! Well I don't have anything against collaboration, paid or not. Off T: open source is really important when it comes to some thing: like computer security & encryption code. I don't agree with the spirit behind GNU though, which insists that people have a right to know how something works makes it so no one could ever add something unique and secret to the code and sell it. I think if you change it, want to keep it secret, okay. On T: If you have a PPL is there anything additional to do for ultra lights? What if a Texas Parasol comes in heavier than UL? Is it then just an experimental category? I am looking at the drawings and so on. Not a very big parts list. Must be cheaper than the teenie two. What do the materials cost for the airframe, about? Really amazing and fun looking. Zuehl, eh? Don't those jets out of Randolph give you guys a fright? |
#64
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VWs
On Wed, 30 Jan 2008 21:27:01 -0800, cavalamb himself
wrote: wrote: Robert Padget's 1/2 VW parasol:http://www.youtube.com/watch?v=eps0zQP2SeE Paul Hammond's 1600 VW parasol:http://www.youtube.com/watch?v=vSxM-BrXnd0 takeoff:http://www.youtube.com/watch?v=se0fRqMUoUc landinghttp://www.youtube.com/watch?v=v-jrHDvyJ4c The trials and tribulations of a new motor (VW)...http://www.youtube.com/watch?v=ckjqfUM5xlw Ah they are your design! Very cool!!! A collaboration of half a dozen guys. (open source?) I drew up the plans and wrote the manual. Not to stir up a hornets nest - but just one question. Has the wing deficiency been addressed? Google and search archives. I won't say any more. Richard knows what I'm talking about He should be able to give you a yes or no, as well as the details of any changes it the answer is yes. If the answer is no, caveat your emptor - do your homework, etc etc etc. Nothing personal, Richard.. -- Posted via a free Usenet account from http://www.teranews.com |
#65
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VWs
Doesn't matter what speed you run the V Dub, the stock cyl heads do
not have enough fin area to shed the heat of more than 40-50HP longterm.. Several of ya'll have referred to "stock" cyclinder heads and not enough fin area. Are there non-stock cylinder heads, then? Since this heating problem has been known since the fifties it seems like somebody would have come up with some heads (and jugs) that have a lot more fin area. Like a Corvair -- or an aero engine. I've seen two european companies that seem to be trying to address the heating limitations of VWs that way. I'm not even thinking here of somebody wanting to do an aero conversion, but, since the aftermarket for VW keeps on going and going that somebody doing racing or dunebuggies or just new or rebuilts for VWs would have done such a head. I've looked on sites like aircooled.net before I ever posted here but did not see. |
#66
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VWs
wrote:
Robert Padget's 1/2 VW parasol:http://www.youtube.com/watch?v=eps0zQP2SeE Paul Hammond's 1600 VW parasol:http://www.youtube.com/watch?v=vSxM-BrXnd0 takeoff:http://www.youtube.com/watch?v=se0fRqMUoUc landinghttp://www.youtube.com/watch?v=v-jrHDvyJ4c The trials and tribulations of a new motor (VW)...http://www.youtube.com/watch?v=ckjqfUM5xlw Hah. Good to have patient friends! Those parasols look fun. I want to look them up on the 'net. What are they? You can find links to the (free!) plans download here. http://www.home.earthlink.net/~cavelamb/parasol.htm |
#67
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VWs
wrote:
Robert Padget's 1/2 VW parasol:http://www.youtube.com/watch?v=eps0zQP2SeE Paul Hammond's 1600 VW parasol:http://www.youtube.com/watch?v=vSxM-BrXnd0 takeoff:http://www.youtube.com/watch?v=se0fRqMUoUc landinghttp://www.youtube.com/watch?v=v-jrHDvyJ4c The trials and tribulations of a new motor (VW)...http://www.youtube.com/watch?v=ckjqfUM5xlw Ah they are your design! Very cool!!! A collaboration of half a dozen guys. (open source?) I drew up the plans and wrote the manual. |
#68
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VWs
On Jan 30, 8:24 pm, wrote:
Are there non-stock cylinder heads, then? ------------------------------------------------------------------------- Yes there are, as a matter of fact. There are a number of after- market heads intended for the HOT-ROD market, designed specifically to deal with the CRACKING problem. They do this by casting the combustion chamber almost half an inch THICKER. Unfortunately, this results in LESS fin-area than before, which makes these heads even LESS useful for flying VW conversions than the stock heads. Enormously popular, of course :-) So why didn't they address the REAL problem of inadequate fin area? Because that would increase either the cost or the SIZE of the cylinder heads. Increase the physical size of the heads and they won't fit the stock shrouding, meaning you'll be forced to modify virtually everything that attaches to the heads -- upper (and lower) shrouding, intake & exhaust manifolding... by which time the heads will be too expensive for the Kiddie Trade, which is what they were designed for to begin with. Or, you can cast the heads as a block and MACHINE the fins so as to give more fin area. Unfortunately, when you do so you run into the same problem of high cost. As for flying VW's and those of us who have forty or more years of working with them, we have tried welding on additional fin-area, the so-called 'Fat Fin' modification -- which DOES work... if you're willing to devote lotsa money & time to it. Or you can read about various experiments with liquid-cooled heads -- which also works... if you can afford the radiator(s), pump(s), plumbing and WEIGHT that goes with it. But do all that you run into a very real -- but subtle -- limitation, in that the BEARING AREA of the VW rods & crank was simply not designed for LONG-TERM RELIABILITY at high levels of output. And there is no work-around for that particular problem, although full- flow oil filtration and the mods to the lubrication system -- that were developed starting in the late 1950's -- provides for some improvement (ie, the HVX mods). Which leaves you with PSRU's -- torque multipliers -- which, in theory, should allow you to operate the engine at higher rpm without exceeding the inherent limitations of the crank & rods. But that's only true if you address the cooling problems in a realistic fashion. Put all that together and you'll have the equivalent of Rotax 912... and for about the same price (!!) ...but at significantly more weight. Don't take my word for any of this. Hit the books. Build some engines. THINK FOR YOURSELF. Get stuck into it, you're only about four years and maybe ten thousand dollars away from REALLY knowing about VW conversions. Of course, once you arrive there no one will believe you anyway :-) People believe what they WANT to be true. And there are plenty of hucksters out there eager to prey upon that ignorance. After eight or ten years of fumbling around you're going to have to decide if you want to spend all of your time tinkering with engines or building an airframe that will probably never fly. Of course, those things reflect the social aspect of homebuilding... which today makes up about 99% of ALL homebuilt activities. If on the off chance you're actually interested in FLYING then simply follow the well-trodden path to a VP-1 or Teenie Two, bang it out -- keeping it as light as possible -- stick a STOCK 1600VW on the nose... and go fly. You don't absolutely need to jump through all the FAA's hoops -- there's no traffic cops in the sky. You will have divorced yourself from the SOCIAL aspects of aviation more than the legal, but if your primary interest is FLYING you will find it's an itch that's pretty easy to scratch. -R.S.Hoover Since this heating problem has been known since the fifties it seems like somebody would have come up with some heads (and jugs) that have a lot more fin area. Like a Corvair -- or an aero engine. I've seen two european companies that seem to be trying to address the heating limitations of VWs that way. I'm not even thinking here of somebody wanting to do an aero conversion, but, since the aftermarket for VW keeps on going and going that somebody doing racing or dunebuggies or just new or rebuilts for VWs would have done such a head. I've looked on sites like aircooled.net before I ever posted here but did not se |
#69
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#70
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VWs
clare at snyder.on.ca wrote:
On Wed, 30 Jan 2008 21:27:01 -0800, cavalamb himself wrote: wrote: Robert Padget's 1/2 VW parasol:http://www.youtube.com/watch?v=eps0zQP2SeE Paul Hammond's 1600 VW parasol:http://www.youtube.com/watch?v=vSxM-BrXnd0 takeoff:http://www.youtube.com/watch?v=se0fRqMUoUc landinghttp://www.youtube.com/watch?v=v-jrHDvyJ4c The trials and tribulations of a new motor (VW)...http://www.youtube.com/watch?v=ckjqfUM5xlw Ah they are your design! Very cool!!! A collaboration of half a dozen guys. (open source?) I drew up the plans and wrote the manual. Not to stir up a hornets nest - but just one question. Has the wing deficiency been addressed? Google and search archives. I won't say any more. Richard knows what I'm talking about He should be able to give you a yes or no, as well as the details of any changes it the answer is yes. If the answer is no, caveat your emptor - do your homework, etc etc etc. Nothing personal, Richard.. Understood, Clare. It's something that has to be addressed. Absolutely no change. And none is needed. And - to the frustration of all nay sayers everywhere - they are all still flying. See, the deal is, with this light of a plane and all the drag, you simply can't pull more than 2 1/2 G's before the thing mushes out. (it's not really a stall either). BUT!!!! If someone really just HAS make it stronger - just because - please feel free to do so. All it takes is a 2-1/4" diameter tube for the front spar and 2-1/8" sleeves. Like I said in the book - "This is how we do it down here". Ok? |
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