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Discussion Starter · #1 ·
Hi everyone I cleaned my intake manifold and got new gaskets. When I installed all of that the car whistles now in low rpm's. It seems like I lost some power too in all the band ranges. Im not sure if the gaskets sealed all the way and some air is leaking out, also I dont know if thats the reason my car lost some of its power. Somebody please help!! Thank You
 

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1999 3.0 SilFro
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If your gaskets didn't seal properly, you WILL get a Check Engine Light soon.
 

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Discussion Starter · #5 ·
Thats the thing its been doing it for awhile and I havent paid no attention to it because the cel didnt turn on for over 10 tanks of gas but im pretty sure its the intake manifold because it used to never whistle before I put the SVT one in. Im thinking maybe of just redoing it all over again just to make sure. I just want my performance back also!
 

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Yeah the SVT manifold is smooth on the inside, so it will whistle a little bit at certain harmonic frequencies.
 

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Yeah the SVT manifold is smooth on the inside, so it will whistle a little bit at certain harmonic frequencies.

Harmonic frequencies.....???

So would that be because the alloy is thinner due to the UIM being honed out that it can no longer absorbs the frequency of the sound waves from the air moving through the intake....

or that it is actually sound from the vibration of the intake itself...
 

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Harmonic frequencies.....???

So would that be because the alloy is thinner due to the UIM being honed out that it can no longer absorbs the frequency of the sound waves from the air moving through the intake....

or that it is actually sound from the vibration of the intake itself...
The inside of the standard manifold is rough - pretty much exaccly like the surface on the outside. The SVT unit is honed to a near-mirror smoothness inside.

It isn't the thin walls or the vibration at all. It's the rush of air that causes the noise. It only happens when the throttle body is at an exact position. Open it up a little further and the noise goes away.
 

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Yeah, definitely the SVT UIM and TB :) It's now loud enough that I can hear the intake over the Borla. If you don't have a CEL by now, it's what Bennett said - the SVT UIM can be heard where the stock UIM couldn't. Enjoy the sound :)
 

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Huh. Maybe my cars too loud to hear it or I'm confusing it with something else. The cold air intake makes a whistle for sure. It's still strange if you're losing power. Honestly, just take it back apart and try reseating everything. That normally works best on vacuum leaks.
 

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The inside of the standard manifold is rough - pretty much exaccly like the surface on the outside. The SVT unit is honed to a near-mirror smoothness inside.

It isn't the thin walls or the vibration at all. It's the rush of air that causes the noise. It only happens when the throttle body is at an exact position. Open it up a little further and the noise goes away.
Well that sounds like a sound I would like to have on my MPV....:biggrin:
 

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It definetely wistle at a ''higher pich'' trought my honed and extrude UIM......... anyhow it's much more than just ram air!!! At first I too tought I have a leek. Now I kinda loving it :biggrin:
 

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Discussion Starter · #17 ·
Yeah Its just kinda loud thats what makes me think its not normal(almost like a supercharger whistle). I will be doing this probably this weekend since I have to rebuy the gaskets to make sure they seat properly. It overpowers the intake also because I do have an AEM short ram.
 
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