I tried doing a sound clip today, but the car mount I have keeps making a nasty rattle. Very annoying! The attached video is exactly how mine sounds after 15lbs of boost. Anything lower just makes a normal whoosh sound.

https://www.youtube.com/watch?v=g2MG...e_gdata_player

 

I'm under the impression that's fluttering. However it's funny that that is a VW. Apparently a lot of VW's do that and it's "fine". Both my buddies GTI and 3zero3 Motorsports has a super duper fast GTI and RS4 that also flutters and they say it's fine. One buddy has over 80k miles and has been tuned and VTA since 20k miles and the other has 40k miles but has a red license and he bought his GTI new in 2007. Got a DWI/DUI a year or two later and he rarely drives. However his GTI is sick, he's put good money into.

So I wonder if it's really bad?

 

I've been wondering the same thing. Maybe the air isn't escaping quick enough at higher boost levels? I'll try the yellow spring.

If you listen closely to this video at 17 seconds you can here it.
https://www.youtube.com/watch?v=FjuM...e_gdata_player

 

I don't know enough about the subject to say anything worth hearing, but if you youtube videos with GTI and BOVs, you'll see some of what I'm talking about.

 

It honestly sounds annoying. Like a school girl crying and running out of breath

The vw not the LNF

 

how do we tune for this ?

 

My Z54 has done this from day one, it's so annoying. It doesn't do it under high boost though, it blows off normally. I was gifted one of the newer bypass valves that is fitted to the newer Z54's (lighter spring) and it still does it. My guess is the LNF just doesn't produce enough vacuum to pull it fully open. I've tried bypassing the vacuum tank, running the vacuum line directly from the manifold, etc. Nothing helps, just turkey gobble all the time lol..