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Flapper Valve

Flapper Valve


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Old 04-03-2005, 1:30 AM
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Flapper Valve
What does that intake flapper valve do? Is it to keep the intake velocity up at low rpm's or is it to keep intake noises down?

Rob

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Old 04-03-2005, 1:53 AM
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Re: Flapper Valve
Read this
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Old 04-03-2005, 2:23 PM
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Re: Flapper Valve
Quote:
Originally Posted by JAMI6989

exactly...... it's an EPA device to stop intake noise. it does more "bad" than good. all i did was put a BB in the vacuum line to stop it from closing. it's open in it's relaxed (no vacuum) position.
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Old 04-03-2005, 4:09 PM
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Re: Flapper Valve
So...none of you guys think it's to speed up the air velocity at low RPMs? Or are you simply believing what was said on the link above?
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Old 04-03-2005, 4:49 PM
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Re: Flapper Valve
Quote:
Originally Posted by nedro
So...none of you guys think it's to speed up the air velocity at low RPMs? Or are you simply believing what was said on the link above?
I don't know enough about how it works to know exactly why but I did it and it does seem to help
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Old 04-03-2005, 5:49 PM
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Re: Flapper Valve
Quote:
Originally Posted by nedro
So...none of you guys think it's to speed up the air velocity at low RPMs? Or are you simply believing what was said on the link above?
It is WFO at low RPM and only closes as the airbox/snorkel combination approach their resonant frequency and then reopens above 7K. For this reason, it wouldn't appear to be restricting airflow at lower rpms for engine tuning, just to dampen the characteristic "honk" the intake system makes between 5500 & 7000 rpm.
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Old 04-03-2005, 7:53 PM
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Re: Flapper Valve
Wow, thanks for the good information.

Rob
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Old 04-03-2005, 10:07 PM
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Re: Flapper Valve
Between 3.5K and 6K RPM the RC resonates at a frequency that will attract cats or aliens (depending on SP1 or SP2) and the flapper cures this.
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Old 04-03-2005, 11:16 PM
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Re: Flapper Valve
Quote:
Originally Posted by sheepofblue
Between 3.5K and 6K RPM the RC resonates at a frequency that will attract cats or aliens (depending on SP1 or SP2) and the flapper cures this.
so by doing the flapper mod, you're stopping the possible attack of cats and/or aliens?

this is gonna be good for my lap times................
Last edited by Rigor : 04-03-2005 at 11:17 PM.
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Old 04-04-2005, 8:21 AM
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Re: Flapper Valve
Quote:
Originally Posted by Rigor
so by doing the flapper mod, you're stopping the possible attack of cats and/or aliens?

this is gonna be good for my lap times................

Wrong. It's the potential for cat and alien attacks that lowers lap times.
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Old 04-04-2005, 9:00 AM
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Re: Flapper Valve
Quote:
Originally Posted by Rigor
so by doing the flapper mod, you're stopping the possible attack of cats and/or aliens?

this is gonna be good for my lap times................
Only aliens as you have an SP2. The cats you need a different solution.
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Old 04-04-2005, 9:31 AM
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Re: Flapper Valve
Yep, no aliens OR cats around mine (00 with 02 updates) . . .
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Old 04-08-2005, 11:24 PM
  #13
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Re: Flapper Valve
Quote:
Originally Posted by nedro
So...none of you guys think it's to speed up the air velocity at low RPMs? Or are you simply believing what was said on the link above?
Ab was right i feel, to speed the velocity you would want it shut down from idle ....... and gradually open up. It runs a diaphram meaning its open ... or closed somewhat with a tiny difference of vac . The fact it also is closed at a certain time .... says its not a velocity thing .
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