Air Intake Black Box?

[l008com]

What is this odd black box next to the air filter on the intake?
It's odd and doesn't seem to do anything. Some have suggested that it is for sound purposes, and removing it will make my engine sound a little better. Is this true?

 

[Mooseman]

Yes and yes. That's the resonator. There's actually two. One is that plastic thing in the middle of the intake and the other is in the airbox itself. I removed mine using 4" silicone tubing and the other I never had since my airbox cover was missing and I didn't get one. Sounds a whole lot better

 

[l008com]

Nobody makes a simple cheap connector piece that doesn't have the side port? I like better sound, and I like removing parts from my truck, even if they're plastic and weigh nothing. Resonators at both ends, is that the reason my V8 suv sounds so un-sports-car-like?

 

[mrrsm]

Your idea to simplify the matter more directly makes perfect sense... except for a little problem that falls in a category of a weird kind of acoustics called "Helmholtz Frequencies". Ordinarily... nobody would EVER convince me either that a Straight Tube from the Air Filter to the Throttle Body and Intake Manifold would NOT be more efficient. But since all engines are essentially Air Pumps... when columns of air are being drawn up inside of each cylinder on the Intake Strokes... they tend to ricochet and bounce back and forth and propagate Sound Waves that can crash into one another and actually rob your engine of real Horse Power in the absence of a "Helmholtz Resonator" to give the waves a place to sort of "level off". So while it might seem to be a "Plastic Box for Old Ladies to Get a Better Sound from their Cars..."... the scientific basis for its presence is well established.

You can demonstrate the principle involved here by simply blowing air across the neck of a Soda Bottle (or Beer Bottle if you prefer). The sound you will hear is being caused by the "Helmholtz Resonance". The lower the level of the fluid in the bottle; the lower the resonant sound frequency will become. Of course, it is possible to bypass the "Acoustical Engineering" involved here... but it will defeat the benefit of having all of the air that literally is bouncing inside of each cylinder and creating acoustic waves that will interfere with the smooth flow of air... and that is where the power of the engine can suffer... especially in an engine that has 12 out of the 24 Valves drawing in air at velocities that can really generate the interference patterns caused by the phenomena. Sometimes... the GM Engineers actually do get it right! ;>)

https://en.wikipedia.org/wiki/Helmholtz_resonance