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Wasted boost

Discussion in 'A4/S4 forum(B5 Chassis)' started by g60leigh, Jun 30, 2008.

  1. g60leigh
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    g60leigh Well-Known Member

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    may be a really daft question this one, but......
    now I have fitted an induction kit I can hear my DV. when running slowly through the rev range I can hear it purging boost. (@ about 5psi)
    is there any point in adjusting my DV spring or is it supposed to be doing this for a vital reason?

    If I should change, any idea which spring to use?
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  2. hiltoa
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    hiltoa VAG erfahren

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    Is this not what the N75 valve controls to smooth out boost delivery?
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  3. jcb
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    jcb Active Member

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    how do you know it is purging boost?
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  4. g60leigh
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    g60leigh Well-Known Member

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    I can hear the hiss now through the cone filter when gently accelerating and the boost gauge shows 5 psi
    if I boot it I run aprox 13-15psi
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  5. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    would seem to me that its just doing its job...

    You have positive pressure and a closed throttle butterfly, you either dump the air thru the valve or you dont and stall out the compressor.

    You might find that the turbo would be fine handling 5psi without the dump valve, but then again they are pretty puny things and i guess they have just specced the valve to be safe
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  6. g60leigh
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    g60leigh Well-Known Member

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    ok best leave things alone before I break something then
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