I've fitted a dump-valve this weekend with the Graham Good fitting kit.. It's a recirc valve and is not supposed to make any sound. I'm not sure about the make, but it looks much like several other makes i've seen that fits the impreza.

At the same time I mounted the samco intercooler hose kit (which by the way looks very cool ;-).

But the problem is.. After I fitted this kit the engine makes a strange whistle sound much like the one you can hear if the wind is blowing strong and your housecorners make whistles..

So i'm just wondering if this dump-valve is not for the impreza.. If the spring in the valve is to strong and the valve doesn't open, what kinda sound would it make?

I'd love to get some feedback on this!..

Anyone know anything about this? I can't be the only guy who has experienced this?

Might be.. It's just that I hear so much strange noises from the engine that i'm getting a bit paranoid.. Maybe I should just lean back and enjoy the whistle instead ;-)

Sorry can't help on your querry. But noticed the aalborg address, it years since I've been there, how is the John Wayne strasse these years, still going all night long?

It's still going strong yes ;-)

Twinny,
A recirc valve will make exactly the same sound as a vent to atmosphere dump valve as they do exactly the same job (i.e. release the excess air pressure).

The diference is that you normally can't hear the recirc dump valve venting due to the fact that it vents back into the intake and not to atmosphere.

You will normally find that if you fit an induction kit in place of the original airbox, you will then be able to hear the standard recirc dump valve operating although it'll be a lot quieter than a VTA.

Andy

If the sound happens whilst you accelerate then its either you hearing the turbo (high pitched whistle), or the valve isn't shut correctly (blowing over a milk bottle).
If it happens when you lift off it can either be the turbo spooling down (in normal driving), or the dump valve working (in full bore upshifts).

You only have a problem if you hear the milk bottle sound.

Hope this helps

Justin

And if it happens at part throttle ONLY then it'll be due to the spring in the valve not being strong enough and allowing the dump valve to open and pass air through when on part throttle.

Andy

I have a little sound-clip here of what it sounds like.. Just check http://www.hjem.no/my99sound.wav and you'll hear it for yourself.. The sound is when I liftoff and not when I accelerate.


[Edited by twinny - 3/16/2002 7:21:52 PM]

Haven't got a sound card on my machine at work and so can't listen until I get home tonight. Sorry

Andy

Did you check the file with your home-computer yesterday?

I don't have an aftermarket dump valve so can't comment ... yet ;) but I do get a nice Turbo whistle and some meaty induction roar from the ITG panel filter :D:D I like it!!

Phil :D

i noticed this chattering noise on my 97 uk model after fitting an induction kit, but it sounded more like a horse !! I suspect the spring in the valve is a little too stiff, and is still bedding in, sounds cool though dont it! i am advised (not sure if correct) that it is the noise of the button on the actuator, and nothing to worry about

Yeah, I agree it sounds a bit cool.. It isn't very loud though.. One can't hear it outside the car I think ;-) But I would'nt know.. I'm usually inside my car when driving ;-)

Hi Twinny,

A DTA valve will make a whoosh on gear changes, the whistle sound usually comes from the Turbo. Perhaps you're just getting a louder Turbo whistle with the re-circulating valve?

I hear a whistle on my MY99 (although it's very descrete) and prefer it to the whooosh from a DTA valve.

Stefan

[Edited by ozzy - 3/11/2002 11:04:54 AM]