I get a whole lot of "Fluttering" with both BOV

[jtk500]

It doesn't matter if I use stock or Greddy type-S BOV. I have AEM short ram installed and with stock BOV everything sounded fine. I installed the Greddy type-S BOV in it's str8 outta the box config. After I had everything hooked back up, I revved the engine up and heard some insane noises that I think is "fluttering". I can hear a rapid "chu..." sound 3 times then whoosh. I later found out that I needed to take out the smaller spring, which I did. It still makes that sound, even after I reinstalled the stock BOV!! It sounds to me like I F$&%ed something up in my intake. I took apart my intake, cleaned it out and put it back on. It still makes the noise and I can't reinstall my stock intake sys. due to the fact that there is a huge hole in it from damage I inflicted on it when I removed it.

[DRFTR8]

I had that same issue, but i didnt have an intake.. i just installed my GFB and it was fluttering... so i check it over and had friends with the same BOV check it over and they even adjusted it... well to make the story short the setting was too tight. even the car blew out the air, the BOV shut too quickly and what was happening was that the air was going back to the turbo making the wheel slow down that what you hear.. its air going back towards the wheel... what you need to do is changed out your spring to a softer one so that it can release more of the air..

[Unowned]

i have the JDM MR bov with AEM intake, and at low rpms (2k) if i shift i will get flutter. I have an 05 so the car doesn't bog or anything, but i recommend you change your driving style if the fluttering bothers you.

[jtk500]

Driving style's not an issue, It does it throughout the power band. The noise just gets quicker and more high pitched at higer RPMs. Basically if I get boost I get that noise.

[earlyapex]

If it does it when you get off the throttle from building boost , it's compressor surge, the bov is adjusted too tight.

If you still got it when you put the stock BOV back on, you either put the stock BOV back on backwards or you have a boost leak.

If it does that sound when you are building boost, the BOV is leaking or you have a boost leak somewhere else.

[jtk500]

The noise comes after I let off the gas. How is it possible to put the stock BOV on backwards? Please explain

[MarkSAE]

Your BOV is supposed to be oriented like below. The top of the BOV is pointed towards the front of the car.

http://www.norcalevo.net/gallery/albums/album209/DSC03560.sized.jpg

[jtk500]

:shock: OMG!

[jtk500]

:bandhead:

[jtk500]

Wait wait... The port of the BOV which has the spring pushing goes to the Recirc. hose and the side port in which the spring passes goes to the intake system?

[earlyapex]

Hold on, let me go take a photo of my spare stock bov and I will label what goes to what.

[earlyapex]

Ok here we go:

http://www.norcalmotorsports.org/users/bryan/mods/EVO/stock_bov/stock_bov_installed.jpg

http://www.norcalmotorsports.org/users/bryan/mods/EVO/stock_bov/stock_bov_loose.jpg

[jtk500]

Wow I DO have it in there backwards, I assume that's the same for the Greddy Type S. Thanks for all the info everybody :D

[earlyapex]

No problem. 8)

[MitsuMan]

the sound you hear is the turbo fins backing up on the presure that wasn't released if the valve is too tight is will do this. also if its backassward cause your not dumping the presure

[DRFTR8]

the sound you hear is the turbo fins backing up on the presure that wasn't released if the valve is too tight is will do this. also if its backassward cause your not dumping the presure

thats what i said...:D

[MitsuMan]

me too :lol:

[earlyapex]

the sound you hear is the turbo fins backing up on the presure that wasn't released if the valve is too tight is will do this. also if its backassward cause your not dumping the presure

Maybe read the whole thread first? Already been answered a couple times.