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Old Jan 23, 2019 | 09:07 AM
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What happens if an engine takes in more air than it can push out?

If you put a high flow air cleaner on but do not change the stock exhaust system as an example.
 
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Old Jan 23, 2019 | 09:13 AM
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You are confused...and has a lot to do with tin men BS .
The engine does not suck in air. The exhaust is the piston coming up and driving it out. (Modern OEM dual exhaust are connected with a cross over that enables one cylinder to share both mufflers and help actually pull some as a side benefit.

The intake is just atmosphere pressure pushing in to fill cylinder . Just like opening you mouth, the atmosphere does not blow out and bust your lungs.

The limit factor is the opening at the butterfly in the throttle body. Even a stock air filter passes all the air engine can use.
I am sure, no air filter may bump HP at WOT but do you do or need that? And it will sound like a Hoover Vac. And that few drops of mist that when setting for a while drip out and down on valve tappet cover or blows back on exhaust.

Do not quote and read and understand my signature please. Just my thoughts and opinions.
 

Last edited by Jackie Paper; Jan 23, 2019 at 09:26 AM.
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Old Jan 23, 2019 | 09:25 AM
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Ok, I will try to answer...

It seems reasonable that an engine cannot take in more air than it can push out. If that is true, then what must happen is at the end of the exhaust stroke there must still be exhaust inside the cylinder when the next intake stroke begins.
 
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Old Jan 23, 2019 | 09:25 AM
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When I do that, the farting gets pretty fierce. If it gets really bad, I sump.
 
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Old Jan 23, 2019 | 09:31 AM
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Originally Posted by BobRR
What happens if an engine takes in more air than it can push out?

If you put a high flow air cleaner on but do not change the stock exhaust system as an example.
A "high flow" air cleaner is a lot like "clean Coal". The throttle body size regulates the air flow into your engine. If you have to much air flow....you have a turbo!
 
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Old Jan 23, 2019 | 09:32 AM
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Originally Posted by RHPAW
When I do that, the farting gets pretty fierce. If it gets really bad, I sump.
..............
 
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Old Jan 23, 2019 | 09:34 AM
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O.P. Spend a few minutes reading ( and a few hours understanding ? ) this.

https://en.wikipedia.org/wiki/Volumetric_efficiency
 
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Old Jan 23, 2019 | 09:34 AM
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Originally Posted by BobRR
What happens if an engine takes in more air than it can push out?

If you put a high flow air cleaner on but do not change the stock exhaust system as an example.
Think about it! Can you inhale more than you can exhale? Obvious answer is NO. Same for any engine.

A high flow air cleaner only alows the engine access to more unrestricted air. Kinda like breathing through your nose is normal, but if you want to take a deep breath you have to open your mouth.

Oh, was this a troll post?
 
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Old Jan 23, 2019 | 09:34 AM
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From: Honah Lee
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Originally Posted by BobRR
Ok, I will try to answer...

It seems reasonable that an engine cannot take in more air than it can push out. If that is true, then what must happen is at the end of the exhaust stroke there must still be exhaust inside the cylinder when the next intake stroke begins.
The piston pushed it out other then that small area at top of piston in the cup area of the head. Even with no pipes, you will have that.
The crossover in the pipes I think help there. I know for some Reas, no crossover seems to kill low rpm torque. Also no engine break when you come off throttle.
I like a street bike fill. Not a racer .
 
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Old Jan 23, 2019 | 09:35 AM
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The cylinder has a set amount of volume remaining at top dead center of the piston stroke. Too much air? More compression. I think the term 'more air' is more apt, too much means you've passed capacity. As was pointed out, exhaust is its function.
 
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