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Discussion Starter #1
So I've been running my GFB VTA Diverter Valve for a few weeks now and I'm getting conflicting and confused feelings as to how the vent to atmosphere "whoosh" sounds like in my car and how it should sound.

I'm not sure if maybe sometimes when I back off the accelerator theres not enough boost built up yet, but some times it gives me pissy little half whoosh/spitting sounds rather than a nice air dumping sound.
Has anyone else experienced this with this particular DV?

I'm not sure if maybe that's how it's meant to sound, or maybe I have a faulty unit? Or maybe that's just the construction of the GFB valve and a different brand valve will sound different/better...

Let me know you thoughts/experiences.

Thanks!

P.s.. i do have a video on my phone of this sound, just not sure how to include this in the post.
 

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I've got the same GFB DV+ 9458.
The BOV is controlled by the ECU so sometimes it may only let off a little bit of boost depending on the circumstances instead of all of it. if you're letting off the throttle at low RPMS then you're not going to get a big whoosh sound, the biggest whooshes will come at high RPM near the rev limit.

Another thing, sometimes if your car is at high rpms and you're going WOT you may hear it let off some boost, that's the ECU trying to keep the PSI under a certain limit so it doesn't harm the engine/turbo.
 

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Discussion Starter #3
I've got the same GFB DV+ 9458.
The BOV is controlled by the ECU so sometimes it may only let off a little bit of boost depending on the circumstances instead of all of it. if you're letting off the throttle at low RPMS then you're not going to get a big whoosh sound, the biggest whooshes will come at high RPM near the rev limit.

Another thing, sometimes if your car is at high rpms and you're going WOT you may hear it let off some boost, that's the ECU trying to keep the PSI under a certain limit so it doesn't harm the engine/turbo.
Thanks for the info..
I suspected that this may of been the case. Its not overly impressive though when it does spit and stutter rather than providing that nice whoosh sound.
Oh well, I've already returned it to GFB for a full refund and purchased the Turbosmart dual port BOV last night. I'll see how this compares when it arrives 😊
 

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oh do post about the t/s unit ... would love to hear about the comparison
 

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Discussion Starter #5
oh do post about the t/s unit ... would love to hear about the comparison
Yep, will do!

Have ordered a few goodies over the last couple of days too. The bank account or the wife aren't overly impressed haha stay tuned!
 

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oh come on what's this wifey schmifey stuff ..... :p
(no disrespect to your "boss" of course)
 

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Discussion Starter #9
Ok so ordered the Turbosmart dual port BOV Wednesday night and it arrived Friday midday.. absolutely lovely!!

First impressions are great, much better sounding that the GFB comparative.Haven't been able to give it a proper test drive as Melbourne's still under stage 4 lockdowns, but so far so good. It's hard to tell without having them on two identical cars side by side, but it kinda sounds like the vent is longer and smoother on the TS BOV (maybe I'm just imagining this).

Would now definitely recommend the TS dual port BOV, should of just gone this route to begin with.
 

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Thats great ... a good start
Do post about how the boost management is
In particular boost recovery with modulated loads
The factory on/off mode was horrible it was like lag on top of lag geewhiz
 
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