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Induction noise - reduction methods

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Old Jan 24, 2011 | 09:04 PM
  #41  
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Originally Posted by richyvrlimited
Excuse my ignorance, but how would this help?
it smooths the transition from earths atmosphere to your intake pipe. when air bends around sharp corners at high speed, it makes noise.
Old Jan 24, 2011 | 09:26 PM
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Originally Posted by y8s
it smooths the transition from earths atmosphere to your intake pipe. when air bends around sharp corners at high speed, it makes noise.
Yup, and if you're on Mars, the atmosphere is thin enough that the noise won't bother you.
Old Jan 25, 2011 | 09:49 AM
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Originally Posted by y8s
it smooths the transition from earths atmosphere to your intake pipe. when air bends around sharp corners at high speed, it makes noise.
Wrong. It's put on the inlet to turbos to make them look bigger and intimidate the guy in the Mustang who wants to see your engine before making some highway pulls. Gosh..get it right Matt.
Old Jan 25, 2011 | 10:27 AM
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Originally Posted by JasonC SBB
Yup, and if you're on Mars, the atmosphere is thin enough that the noise won't bother you.
if you're on mars and sucking in earth's atmosphere, you should put up with the noise.
Old Jan 25, 2011 | 10:35 AM
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Originally Posted by y8s
if you're on mars and sucking in earth's atmosphere, you are making some serious ******* horsepower.
Fixed
Old Jan 25, 2011 | 11:30 AM
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This thread makes me laugh, it has brightened my day

OP - post pics of engine bay
Old Jan 25, 2011 | 05:03 PM
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Yeah, I kinda expected ribbing, I've done the same myself in the past when someone has asked something similar, but I'm older and more irritable now

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Note the airfilter is now near the headlamp lid and the pipework follows the wing (in an attempt to lengthen it and reduce the noise.
Old Jan 25, 2011 | 05:41 PM
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the corrugated tube aint helping...
Old Jan 25, 2011 | 05:53 PM
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It's gone now

Why doesn't it help? I've heard anecdotal evidence that it helps!
Old Jan 25, 2011 | 05:53 PM
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double post
Old Jan 25, 2011 | 07:39 PM
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Ribs create friction, friction causes resonant turbulance, energy lost to turbulance is converted to sound and heat.

Your original post suggests that you are trying to combat "whine" instead of "whooshing" - is this correct?
Old Jan 26, 2011 | 03:58 AM
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yeah reduce the whine, It must be possible as my old mans car barely murmers (granted it's a smaller blower spinning slower but still I don't expect silence, just a nice reduction).
Old Jan 26, 2011 | 10:55 AM
  #53  
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The fact that whine is a higher frequency than an exhaust or intake note, should make muffling it a bit easier.
Old Jan 26, 2011 | 05:59 PM
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Look up a helmholtz resonator (spelling??) . Ever noticed some stock intakes have a random tube that leads to nowhere and dead ends? This is a helmholtz resonator. It cancels out a specific frequency very well. If you do your research you will find some simplified equations which will give you tube length based on wavelength. Of course you would need to know the frequency that the noise is at before you could cancel it.
Old Jan 26, 2011 | 06:24 PM
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rebuild the supercharger
Old Jan 26, 2011 | 06:27 PM
  #56  
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helmholtz resonators work over a narrow freq range. They don't work well if your 'charger whines from 4000~7000 engine RPM.

Broadband absorbers work over wider ranges.
Old Jan 26, 2011 | 07:17 PM
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true. Most acoustic resonator style sound cancellation techniques are "tuned"
Old Jan 27, 2011 | 03:37 AM
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Originally Posted by fooger03
rebuild the supercharger
Yeah err it's not that, it's been completely stripped and rebuilt very recently.
Old Jan 27, 2011 | 08:43 AM
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Just yell at it to shut up when you're driving down the road...



Ahhh you make me think about the unthrottled M45 I had and how it sounded like a firetruck coming down the street
Old Jan 27, 2011 | 12:00 PM
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Maybe something on the underside of the hood? S2000's have a foam pad thing on the underside of the hood which definitely helps to surpress engine noise. Something like that would certainly help (as long as it isn't flamable).




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