may be a dumb question...

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Mar 29, 2004 | 03:45 PM

ralley

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may be a dumb question...

When you put a larger (front mount) IC in you lose 1-2 psi from what I understand. If you have a boost controller can you readjust the boost to compensate the loss?

Mar 29, 2004 | 04:33 PM

Audi2ptzero

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Pressure does not equal air flow.

You might lose a few psi but that also comes with lower the air temps after the fmic. Your not going to lose power because of the lower psi, your actually going to gain since the air temps are lower and you can run a little more adv timing.

Mar 30, 2004 | 05:21 AM

~~ModifiedA4~~

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question on the same topic....

when an IC is spec'd at 1-2psi loss...

thats the loss due to turbulence in the IC and not the thermodynamic loss, right?

Mar 30, 2004 | 06:57 AM

QCRAZY

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That's the pressure drop through the IC at the specified air flow (flow loss).

Mar 30, 2004 | 07:03 AM

cuatrokoop

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Re: question on the same topic....

You can have turbulence in either a factory or aftermarket IC. Just depends on the core length and flow velocity. Critical Reynolds number for turbulent internal (pipe) flow to occur in steady state is 2300. Doesn't take much to reach that with air going through an engine.

The pressure drop is a function of the length more so than anything else, as the restriction size (tube "diameter") is pretty much fixed for IC cores that I have seen.