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Old 08-23-2009, 12:53 AM
  #30  
maxflo777
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Join Date: Apr 2009
Posts: 380
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maximo, I really dont know like you said, I dont have THAT system in front of me, but really, how is it possible that the rotary valve in this design opens completely or enogh for any substantial flow with 2 deg of crank rotaion? look at the picture! just rotate it in your mind with out david blaine in the room and you will see, who cares what they say, its simple mechanics that can be seen from the picture, its almost exactly like opening our 2stroke crankshafts(?), but worst, divided by 2, how can 1 degree of camshaft rotation open up a rotary valve that is about 90 degrees of its circumference? I dont see it man. It will probably take about 90 deg of rotation to open the valve to full flow,then the valve will be there for an instant (ok, unless the valve is expossed completely in the chamber like it is in the upper section of the picture for, I dont know, about 90 deg? - but then compression goes to the trash and piston weight tothe roof trying to get the compression back) and then it will be the other 90 deg closing it.
Only with that disadvantage the system probably can be easely bettered by a good poppet cam, a good roller cam can open a valve at least ~90% of full flow in ~10 -15 deg not 34 like an engine designed for swirl and low end torque. One of us really does not understand something here because to me this is more than simple when applyed, dont get me wrong, it can be me its just that I gave a lot of thought to that type of design years ago with big-name people that really know their stuff and at the end of the day there where two things that the system did not do with any effyciency - opening/closing the valves (extremely slow and again linear and cooling /lubricating the exhaust valve, look at the struggles that the wankle engine has had through its life span to keep its act clean and fuel efficient.
In our earlyer designs our rotary valves even had that same exact round shape in the opening and closing faces and then we noticed that the port opens "quicker" only because it robs it from the area under the curve, the thing that gives you all the power. Im telling you Ive been there.
Im telling you, if it where good the big dogs would be using it, a lot of people do a lot of mind burnouts over that design and end up with the classic power maker. I'm a proud one , dont worry, theres space for you

And just for the record, that head probably requires a different ehaust manifold/header, and different intake manifold, and it obviouslly has a diferent cam, if you put a good head/cam/intake/hearder combination to a 5L ford you can obtain 500 to 550hp, and thats done every day just take alook at any mustang mag. if you do the really trick stuff you can get 750 from 302 cubic inches, again, its been done every day, no turbos or alcohol or nitro, just high octain gasoline, compression and flow.

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