one for the techies re atmos dump valve, sorry again

[antgti]

Right here goes, i am still hell bent on getting an atmospherice dump valve for my FR, 1.8T, on saturday my mate was fitting two dump valves (yes two) and a front mounted intercooler on to a punto GT.  He had a bailey lying on the side so i decided to try it, now it worked no problem at all, and made the lovely whoosh noise, the only thing was after it had dumped there was a very faint sqeaky  noise as the engine returned to idle, almost like air escaping from the system somewhere, the car ran fine and no loss of performance just this strange noise, that was louder if the car was revved at stand still.  When i re connected the re-circ valve there was no noise at all, only when i had the atmos valve on.  

So firstly does anyone know what this sound may be, and could it be causing damamge (i can't see that it can) secondly, impossible perfomance offer a Turbo XS type s dump valve which they say works no probs, but they say not to use it on drive by wire engines, why is that and why would there be a difference,

Please help appreciated, i can't believe its that impossible to have the whooshy noise.

One for tophuh i reckon

[topher]

Assuming it was fitted properly and the connections were nice and tight, then logically the noise will be coming from the re-circ pipe that would be fitted to where the "trumpet" is on the Bailey piece. If it's left there hanging and you didn't clamp it off that's all I can think it might be. You say it ran fine with no detrimental effects, but it'll be showing up a fault code of some sort, and maybe with prolonged use you'll find the car holding back on the boost as it thinks there's a problem.

As for the Turbo XS (which by the way sounds a little fast 'n' furious   ), DBW engines have an additional map sensor in the manifold giving the ECU a much more intricate set of readings, whereas the Non-DBW's will simply overlook/ignore the "fault"
Ideally you want to find someone local with vagcom so you can see for yourself what effects each type of valve is having on the boost management.

Chris.