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N75 valve replaced, now I have 5 psi more boost?

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Old 03-19-2009, 08:15 AM
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Default N75 valve replaced, now I have 5 psi more boost?

I was only making about 11~12psi boost reading wonderful Modschack boost gauge. Car wasn't throwing any codes but it used to boost 12~14psi. I replace my N75 "C" valve with a "H" valve from my old AAN Turbo 5 and now I get build to 18psi with it settling at about 17~17.5 psi. I wonder if the old valve was just bad? Do you guys think my car is chipped? Can just the "H" valve do this much on its own? If they are stock chips will my fuel curves be way off with this much boost? The car builds boost great now, no spikes, just smooth.
Old 03-19-2009, 10:13 AM
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If you are stock you are riding the edge of throwing a code at that level of boost.

Must be very careful what I say as I can no longer edit my response.
Old 03-19-2009, 10:17 AM
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I do have Vagcom so I will check, does anyone know of anyway to check to see if my car has been chipped/flashed? Anyone else running the "H" valve? I don't know of any Vag way to check on the software.
Old 03-19-2009, 12:49 PM
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Anyone else have advice or input on this? Please?
Old 03-20-2009, 10:51 AM
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Default not chipped...that's what is designed to do

the H valve is made to increase the boost a little by lowering the duty cycle on the valve. There fore boost can shoot up and stay a little higher before it will bring it back in check. I think the duty cycle can be equated to the amount of time the valve is checking itself to when its' not. So if you DC is high, the valve is always monitoring and the boost will rise a lot slower and will be very exact. If you lower the DC as they did with the HValve, it doesn't look as much and it can shoot up to higher boost before it says, hey, check that. They it also brings things back down slower because it's not watching it as much...thus a higher boost across the rpm. That Hvalve is no way a direct oem replacemnt...
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