Missing 3-4 psi - N75 valve ??

2.7 V6 30v biturbo - 251bhp
2.7 V6 30v biturbo - 261bhp
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AdamS4
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Missing 3-4 psi - N75 valve ??

Post by AdamS4 » Mon Apr 21, 2008 6:41 pm

Noticed on the Vag Com logs yesterday on the way to the RR and from today's logs, that i'm down on boost by about 3-4 psi from the standard boost.

Could my N75 valve be knackered ?

Might explain why i'm down on power a little.....

BTW, this is my RR graph from yesterday:

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RE: Missing 3-4 psi - N75 valve ??

Post by Blue_Thunder » Mon Apr 21, 2008 6:49 pm

Has it been pressure tested recently?
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RE: Missing 3-4 psi - N75 valve ??

Post by AdamS4 » Mon Apr 21, 2008 6:59 pm

Actually, not for a few weeks... I'll do that tomorrow.
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RE: Missing 3-4 psi - N75 valve ??

Post by GrahamS4 » Mon Apr 21, 2008 8:17 pm

Not for a few weeks!!? I can just see you at the petrol station, right full tank, lets have a quick pressure test!
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RE: Missing 3-4 psi - N75 valve ??

Post by Virdee Autos » Mon Apr 21, 2008 8:24 pm

I've yet to do mine, for even the first time, and here's someone who does it weekly....only joking :D
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RE: Missing 3-4 psi - N75 valve ??

Post by GHH » Tue Apr 22, 2008 11:14 am

interesting to see a printout from another dastek r/r for a stock engine, had mine done on one in march, the plots are pretty much the same on yours as mine, with the high and low points on the graph in the same places. http://i49.photobucket.com/albums/f261/ ... age1rr.jpg

would make sense if it was something to do with the n75 i would have thought. would the timing effect boost reading at all?
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RE: Missing 3-4 psi - N75 valve ??

Post by AdamS4 » Tue Apr 22, 2008 11:41 am

GHH, was yours standard when that RR was done ??

My torque is quite low compares to yours.
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RE: Missing 3-4 psi - N75 valve ??

Post by AdamS4 » Tue Apr 22, 2008 12:58 pm

Just done a pressure test.... all ok from what i can see/hear.

Time to order a new N75 valve ??
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RE: Missing 3-4 psi - N75 valve ??

Post by Blue_Thunder » Tue Apr 22, 2008 2:15 pm

Why not, it's not a lot of money for piece of mind, even if it doesn't fix the issue.
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RE: Missing 3-4 psi - N75 valve ??

Post by AdamS4 » Tue Apr 22, 2008 3:38 pm

Cheers, ordered one :D
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Re: RE: Missing 3-4 psi - N75 valve ??

Post by GHH » Tue Apr 22, 2008 11:56 pm

AdamS4 wrote:GHH, was yours standard when that RR was done ??

My torque is quite low compares to yours.
its standard bar 710N's, fully decatted stock system, RS2 plugs and some holes in my airbox 8)

off topic but i fitted an awe vent guage today, looks well smart and never had boost guage before :D what boost should a standard car make anyway?

George
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RE: Re: RE: Missing 3-4 psi - N75 valve ??

Post by AdamS4 » Wed Apr 23, 2008 8:36 am

11 psi..... i think
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RE: Re: RE: Missing 3-4 psi - N75 valve ??

Post by GHH » Wed Apr 23, 2008 11:33 am

oh mines reading about 10 psi max....i've lost one too! altho think it was fine on Vag Com so wont worry too much.
hope the N75 valve sorts it mate.
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RE: Re: RE: Missing 3-4 psi - N75 valve ??

Post by Ads4 » Wed Apr 23, 2008 11:54 am

The N75 valve was holding mine back too when Doug remapped it after the manifolds. The missing psi returned with the new valve :beerchug:
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RE: Re: RE: Missing 3-4 psi - N75 valve ??

Post by S4 » Wed Apr 23, 2008 12:20 pm

Turn the screw..... if you dare .............................................................................................

Darren
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