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kleenex
07-12-2006, 04:18 PM
Hey guys
ive recently just put on a HKS SQV bov and for some odd reason i still get flutter. Im only running 8psi on a d16y
revved the engine and i still hear the flutter around the FMIC
ive placed the BOV between the throttle body and the FMIC
am i losing boost or not enought pressure:confused::confused:

DLO01
07-12-2006, 04:39 PM
Placement is fine.
If its fluttering, the boost is blowing off back through the turbo compressor wheel.
Is that BOV adjustable?

I see maybe 2 things that i could be:

Either the Spring is adjusted on 'too hard' on the BOV and you need to loosen it up.

Or have you got the Vacuum hose 'pull' hooked up from you IM to BOV? When the butterfly is closed (off throttle) the vacuume in the IM will suck and pull the BOV open.

kleenex
07-12-2006, 04:47 PM
thanks for the reply
the BOV is adjustable and ive adjusted many setting to loose to tight and still flutter

i dont get what u said in the second bit? im a bit lost

seihoa
07-12-2006, 05:07 PM
it will always flutter because u have an atmo bov if u want to stop it fluttering get a plump back bov = ]

DLO01
07-12-2006, 05:12 PM
Your BOV does not just work on PUSH boost pressure alone.

Its a PUSH, PULL oppreration.

You SHOULD have a pipe from your BOV to your Intake Manifold (IM)

Under acceleration the Butterfly is open, so for example you have 8psi at your BOV and in your IM. The force PUSHING against the BOV from one side is 8psi and there is also equal pressure 8psi PUSHING on the other side from the IM. They are pushing against each other and therefore cancel each other out, hence the BOV rightly stays closed under acceleration.

When you change gears. The Butterfly is closed, you still have 8psi pushing against the BOV on one side. In the IM the butterfly in the Throttle body is now closed causeing a negative pressure in the IM. Pressure on Pushing on the BOV on one side as well as pulling on the BOV from the other side IM, This will open the BOV releasing pressue.

I think you just have not hooked up this hose. Thats your problem. :thumbsup:

DLO01
07-12-2006, 05:13 PM
it will always flutter because u have an atmo bov if u want to stop it fluttering get a plump back bov = ]
Wrong. You will only get flutter from blowing back through the Turbo, through the fins on the Compressor Wheel, hence the BOV is not working.

JasonGilholme
07-12-2006, 05:17 PM
Might want to post up a pic of your engine bay/BOV.

As dean said. your probably missing the vac line off the BOV.

DLO01
07-12-2006, 05:32 PM
This is the PULL vacuum hose connection to IM.

http://i13.photobucket.com/albums/a265/DLO01/Temp/Copyofbov.jpg

seihoa
07-12-2006, 05:39 PM
if he didnt connect the vac the bov wouldnt work still would it ?
never tried it ....
anyways it will always flutter due to it being an atmo bov since there isnt enough pressure to open the bov at low boost and if u adjust the bov to too soft the bov could leak at low boost wouldnt it or would cause a rough idle O_o

im still new with turbos dont mind me its jst wat i thought = ]

JasonGilholme
07-12-2006, 05:47 PM
it will work to some degree.

It may not release all the boost from the pressured side of the turbo. and it may also leak boost when under full load beacuse theres nothing pushing it shut from the other side.

DLO01
07-12-2006, 05:47 PM
Its an installation error. If it is installed & adjusted correctly the BOV is either of 2 things Hard Closed or Hard Open. You don't get flutter with both those senarios.

Once again, flutter is boost escaping Off Throttle back through the turbo. Which can be from having no BOV installed at all, a BOV adjusted too hard or as above, without the Vac line installed.

kleenex
07-12-2006, 07:59 PM
ive got the vacuum hose all hooked up to IM
im pretty sure all conections are there
i hooked up the BOV to my mates wrx and it does work so its not faulty i guess
even if i take off the BOV its exactly the same flutter, in terms of pitch etc. There seems to be no difference if i take it off or not

JasonGilholme
07-12-2006, 09:11 PM
sounds like faulty springs in the BOV then

DLO01
08-12-2006, 08:00 AM
ive got the vacuum hose all hooked up to IM
im pretty sure all conections are there
i hooked up the BOV to my mates wrx and it does work so its not faulty i guess
even if i take off the BOV its exactly the same flutter, in terms of pitch etc. There seems to be no difference if i take it off or not

Yeh, its not working still. Theres something still wrong. Still think its something to do with the Vacuum side. Just can't tell without looking at it.

-MuGen PoWer-
08-12-2006, 09:49 AM
Is that a HKS or HKS copy?
The bolt looks like its gona fall off.
maybe the spring is faulty or stuffed?
8psi isnt much to open the BOV so you should expect flutter as well as the BOV venting.

seihoa
08-12-2006, 09:52 AM
Is that a HKS or HKS copy?
The bolt looks like its gona fall off.
maybe the spring is faulty or stuffed?
8psi isnt much to open the BOV so you should expect flutter as well as the BOV venting.

yep yep i reckon its the ATMO bov which is causing it to flutter due to not having enough boost to keep it open and release all the pressure = ]

does the BOV work tho?

kleenex
08-12-2006, 03:06 PM
yup the BOV works fine on my mates wrx
possible reason is that i might be leaking boost??

rexedup
18-12-2006, 04:49 PM
i reckon the spring is too hard, 8 pounds is low and if theres flutter the bov isnt opening because not enough pressure because the spring is too hard for your application, sure u can adjust it, but adjusting is limited in range, they do sell different spring tensions, so you could prolly get a softer one, it most likely works fine on your mates wrx because they run much more boost, around 15-16 pounds usually, which will force the bov to open, whereas if they were using 8 pounds they might have trouble having the bov open as well, and at the end of the day, most bov's are universal, and not all cars are created equally, so they may suit some and may not suit others, the best bov's are oem ones

DLO01
18-12-2006, 04:58 PM
I agree with you Rexedup. I was chatting with Kleenex on Msn, seems as though it is hooked up fine and we came to the desicion that it is the Spring. He has loosened it off as far as he goes and it still flutters. His Bov must be for higher boost applications.

Sexc86
18-12-2006, 05:27 PM
Mate i used one of those HKS ssq on my D15b7 on 8psi... same problem... first of all i think they are a CRAP bov... recommend a greddy type s or something similar... but yes i think they are suited for higher capacity motors and/or higher boost applications