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Discussion Starter #1
Anyone know what the air box on top of the battery is for or what does it do?.
If there is a cube forum or i am posting in the wrong spot please direct me to the right area.
 

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The air box you're referring to is a resonator in your intake which is technically known as a Helmholz resonator, an acoustic device used to control pressure wave harmonics. Air bouncing back out of your engine and into the intake tube doesn't do it in a single pulse the way it would in a single intake runner; the multiple pistons put out pressure waves at their own intervals, and some of those are going to try to bounce back in while others are going out. The result is a "clog" or high pressure area in your intake tube that ultimately limits airflow through almost the entire rpm spectrum.

Adding an expansion chamber to the intake tube forces air coming back out of the engine to slow down to fill the cavity, thus expending a great deal of its energy and slowing the pressure wave reversion. This slowdown allows fresh air to flow toward the engine without fighting pressure reversion waves the entire way, thus aiding in cylinder filling. Since these pressure waves are essentially sound, giving them a place to expend their energy before exiting the air filter box ends up dampening the intake noise and quieting the engine. Thus, the resonator helps to make the engine paradoxically quieter and more powerful.

How's that for an explanation. "knowledge is power".
 

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Registered
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6 Posts
Discussion Starter #3
The air box you're referring to is a resonator in your intake which is technically known as a Helmholz resonator, an acoustic device used to control pressure wave harmonics. Air bouncing back out of your engine and into the intake tube doesn't do it in a single pulse the way it would in a single intake runner; the multiple pistons put out pressure waves at their own intervals, and some of those are going to try to bounce back in while others are going out. The result is a "clog" or high pressure area in your intake tube that ultimately limits airflow through almost the entire rpm spectrum.

Adding an expansion chamber to the intake tube forces air coming back out of the engine to slow down to fill the cavity, thus expending a great deal of its energy and slowing the pressure wave reversion. This slowdown allows fresh air to flow toward the engine without fighting pressure reversion waves the entire way, thus aiding in cylinder filling. Since these pressure waves are essentially sound, giving them a place to expend their energy before exiting the air filter box ends up dampening the intake noise and quieting the engine. Thus, the resonator helps to make the engine paradoxically quieter and more powerful.

How's that for an explanation. "knowledge is power".
Thanks for the info.Can't ask for more than that.So that would mean that the aftermarket air pipe with the filter on the end is essentially not a good idea at all?.
 
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