air filters
Outstanding HDF Member
Joined: Aug 2012
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From: Detroit
Same thing. And with either, a higher pressure differential produces increased suckage.
Outstanding HDF Member
Joined: Dec 2012
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From: Texas
...
Another example: wings of an airplane dont technically create greater pressure under the wing to cause the airplane to fly. Rather, the design of the fixed wing forces air over the top of the wing to take LONGER to flow over the wing than the air underneath. This effect creates a lower pressure area above the wing than atmosphere and allows the aircraft to be "lifted" into the air by the normal pressure of atmosphere.
Another example: wings of an airplane dont technically create greater pressure under the wing to cause the airplane to fly. Rather, the design of the fixed wing forces air over the top of the wing to take LONGER to flow over the wing than the air underneath. This effect creates a lower pressure area above the wing than atmosphere and allows the aircraft to be "lifted" into the air by the normal pressure of atmosphere.
Novice
Joined: Dec 2013
Posts: 19
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From: Belmont NH
Do a little research on what I am saying. That is why a carb or open loop fuel injected bike does not run with near the HP at the top of Pike's Peak as it does at sea level. You cannot get any more then atmospheric pressure in the cylinder with the intake open and the piston all the way to the bottom. When the piston goes down with the intake open, it creates a vacuum. The outside air pressure rushes in from the 14.7 psi or so atmospheric pressure . Now when it comes back up, and compresses, then it does push..but it does not pull in. What I am trying to say to the fp (not you) is that the opened rolled out filter area is not that much smaller then the largest open area at the venturi area of the throttle body.
Seasoned HDF Member
Joined: Mar 2010
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From: Honah Lee
Not sure why ever one needs to address my opinion..sale loopie on the open Hoover Vaccum cleaner sounding filter, porting, polishing, 5 angle valve job or all the other bells and whistles. I am sure it will add HP like you say. Mine has the SE filter along with the other SE stuff in it, but I see little difference in it and my friend Stock Fatboy. However, I never get over 3K unless it's in 5 gear on the interstate. Never hit the rev limiter. Too old for that. So with me, it serves no purpose since my throttle body is rarely open more the a 1/3. Now if it were WOT, sure, I guess it helps to have an open filter and no backing plate. Know when you hold the filter up to a light, you can see the openings in it. However has not hurt anything since my bike has 40K and runs like new and compression at last check (around 34K) was to factory spec.
Outstanding HDF Member
Joined: Aug 2012
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From: Detroit
Another example: wings of an airplane dont technically create greater pressure under the wing to cause the airplane to fly. Rather, the design of the fixed wing forces air over the top of the wing to take LONGER to flow over the wing than the air underneath. This effect creates a lower pressure area above the wing than atmosphere and allows the aircraft to be "lifted" into the air by the normal pressure of atmosphere.
So if we put "technically correct" high volutin' engineering school descriptions aside for a moment, and try to describe wing lift in common language, an airplane wing basically gets "sucked up", just like air gets sucked into an engine. Is there really a better way to describe it than that?
Last edited by Warp Factor; Jan 4, 2014 at 08:22 PM.
Cruiser
Joined: May 2012
Posts: 203
Likes: 7
From: Arizona
Do a little research on what I am saying. That is why a carb or open loop fuel injected bike does not run with near the HP at the top of Pike's Peak as it does at sea level. You cannot get any more then atmospheric pressure in the cylinder with the intake open and the piston all the way to the bottom. When the piston goes down with the intake open, it creates a vacuum. The outside air pressure rushes in from the 14.7 psi or so atmospheric pressure . Now when it comes back up, and compresses, then it does push..but it does not pull in. What I am trying to say to the fp (not you) is that the opened rolled out filter area is not that much smaller then the largest open area at the venturi area of the throttle body.
Road Warrior
Joined: May 2007
Posts: 1,620
Likes: 117
From: ARIZONA
So an airplane wing basically produces lift because of a pressure differential between the upper and lower surfaces. Doesn't matter much which surface is below atmospheric pressure, as long as pressure on the lower surface is higher.
So if we put "technically correct" high volutin' engineering school descriptions aside for a moment, and try to describe wing lift in common language, an airplane wing basically gets "sucked up", just like air gets sucked into an engine. Is there really a better way to describe it than that?
So if we put "technically correct" high volutin' engineering school descriptions aside for a moment, and try to describe wing lift in common language, an airplane wing basically gets "sucked up", just like air gets sucked into an engine. Is there really a better way to describe it than that?
"Those wings generate a whole lotta suck!" ... doesnt have the same ring to it
lololol, damn helos, they ALWAYS mess things up!
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Tourer
Joined: May 2013
Posts: 365
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From: under a rock in the swamp
Do a little research on what I am saying. That is why a carb or open loop fuel injected bike does not run with near the HP at the top of Pike's Peak as it does at sea level. You cannot get any more then atmospheric pressure in the cylinder with the intake open and the piston all the way to the bottom. When the piston goes down with the intake open, it creates a vacuum. The outside air pressure rushes in from the 14.7 psi or so atmospheric pressure . Now when it comes back up, and compresses, then it does push..but it does not pull in. What I am trying to say to the fp (not you) is that the opened rolled out filter area is not that much smaller then the largest open area at the venturi area of the throttle body.
Ripsaw i think the reason bikes do not run as good at the top of pikes peak or and very high elevation has little with atmospheric pressure and a lot more to do with oxygen concentration. Using the the idea of atmospheric pressure why then can't a supercharged aircraft engine wich by nature is being forced feed air still not have a flight ceiling as high as a jet motor? In drag racing the adjust for O2 concentration on top fuelers wich have supercharged engines, Again it nothing to do with atmosphere pressure but the oxygen content of the air.