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I didnt think the BOV had anything to do with 'fluttering,' it's sound is the woooossshhh

I thought the actual fluttering was caused by the intercooler somehow? I think with the air getting trapped with a sudden release of acceleration backing up air?

Maybe trbo32 backs me up when he stated that 'WRX's come out of the factory with no BOV.'

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What iv found is the same people that think running no BOV is the total end of your turbos life are the same people that dont consider changing their oil and filter regularly

Change oil AND filter RELIGOUSLY every 5000, i belive that is more of a KEY POINT for turbo longevity than a bov

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I have heard a lot of high performace cars running with the flutter sound. WRX's come out of the factory with no BOV.  

I guess it comes down to how you want to treat your turbo. I have heard of cases were turbos were running high boost and the driver let of the accelrator and the intake of the air bent the impeller blades back, stuffed the turbo. But these are in extreme cases.

Not sure what i'm going to do.

Does anyone know how to block the stock BOV on a R32 GTS-t?

Also, are you able to make the stock BOV dump to atmosphere?

Dude, Wrx's DO have BOV's, situated on the lefthand front edge of the intercooloer

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personally I find that fluttering sound annoying... its like a low self esteemed persons way of heralding their stock turbo car.

Just get a real good plumb back BOV, maybe even a HKS electronically adjustable BOV (now that's a nice piece of eqipment). That way you stay road legal and you dun have to hide shit from the cops.

The only thing more annoying than fluttering BOV's is people who make the fluttering noises with their mouths... ffs at least learn to mouth a very large external wastegate... speaking of which... if you wanna show a riced up VL a thing or two, get a new manifold and an external wastegate (obviously not road legal but shmeh, at least its well hidden not brightly coloured saying look at me, I am BOV, hear me flutter) then when he revs his engine to make his fluttering noises you could do the same and send him deaf.

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R31Nismoid- The R31 GTS-Rs did not come from the factory with a blow-off valve. Very few cars at the time did. You are 100% right about the turbos being rebuilt all the time.

Yeah... i thought a much, even though the GTS/GTS-x's came with a plumb back one :P

just like the R32's

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Ok, I’ll get over the total flogging I just got for saying that WRXs came out with no BOV. I'm sorry if my facts aren't straight for all you know it all legends out there.

I was only commenting on what a WRX dealer told me when my mate was looking at buying one.

Excuse me for not knowing how to place quotes in the forum.

get your facts straight first.

how well you treat your turbo?

so what, your never going to make boost with it so it's stays like brand new???

Ok R31Nismoid, Obviously I was referring to the wear a turbo will receive if you don't run a BOV as this thread is about BOV and not about running high boost or no boost!!

A turbo will inevitably die anyhow. BOV or no BOV. How long this is... well that could be debated for ever.

It's like how long is a piece of string.

With no BOV it'll just bring it on a little sooner.

How much sooner is so variable and debatable I’m not going to go into it as it'll always be one side vs another.

Look at my car's turbo... it's ROOTED, it's been running no BOV and it's totally buggered.

I'm 99% certain that when I get my new turbo, run a BOV, that it will be far more beneficial for the car and turbo.

Isn’t that just what I was saying when I said it depends on how well you treat your turbo. I didn’t go all that, like you did, but that is what I was trying to say. Maybe you should read the posts twice as not to repeat what has already been said!!

And yeah people have mentioned this topic a numerous amount of times at this forum, so sue me if I want to ask a question.

ALL turbo car's in the 90's come out with a BOV. INCLUDING WRX's.

just because you cant hear the big PSSHT... of the after market BOV as it's a plumb back (as all factory BOV's are), shows you obviously don’t know what your listening for.

Mate, I drive and own an R32 Skyline with a plump back BOV and I know how a BOV sounds whether it's dumping to atmo or running a return line.

I don’t appreciate being patronised, especially in a place like this. A lot of people rely on the advise and comments people make, as they come here because they are interested in their vehicle. They hope that people don’t pass judgement on them or degrade them just because they say something that might not be as accurate as they thought. If I knew all the facts then I wouldn’t be hear asking questions would I.

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trbo32 - As one of the 'know it all legends' I accept your apology.lol.

I don't think anyone was having a go at you or patronising you. You were simply corrected.

R31Nismoid - No R31s came with a BOV from the factory.

trbo32 - Now you just watch what happens now. R31Nismoid will accept my above statement like a man, just as I have accepted his corrections in the past. Neither of us will jump up and down like children because we are all here to help each other and learn from each other. :Pres-hit:

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R31Nismoid - No R31s came with a BOV from the factory.

HHm... We'll ya learn something new all the time. :D

I thought mine (the old copue i had) did have one as i never heard a flutter out of it once... that was running aprox 11-12psi in the end and still nothing.

the big HRRRRRMMMMMMMMMM comes out now :P :confused:

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The filter box and snorkel on these cars does a great job of killing these induction noises. Until I modified my intake I had never heard a flutter either.

If you take the snorkel off and turn the lid of the filter box so that it sucks from behind the washer bottle you can hear it clearly, because the space behind the front quarter panel amplifies it.

HHm... We'll ya learn something new all the time.
lol :P
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Meh, i got a GTS-R now.

And it's getting treated to an expensive turbo (well expensive enough for me) so no more flutter.

Only BOV... gotta get the most miles i can outta this one

That old coupe is gone now, to another home :)

Not gonna try track it down just so i can rip off the airbox and hear it flutter (or not) :P

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jeeeeez there's alot of bullshit that get pushed around these forums and not many of us are experts but we all believe we're right.

My theory is delevoped from talking to so called experts and I believe it makes sense.

No.1 The fluttering sound is better termed wastegate chatter! It is there air pressure in the turbo and intercooler system building and escaping thru the internal wastegate of the turbo when a sudden lift of will cause these internal pressures to rise rapidly and open the wastegate at the set level by your boost control.

No.2 The sound varies from car to car and turbo to turbo depending on intercooler core size, tract length, turbo size, wastegate actuator type, boost controller and boost level.

No.3 My particular set up has a very tight and quick chatter on lift of at any time when the boost level has not been reached and therefore the internal wastegate is closed. When the set boost level has been reached and the internal wastegate is wide open and you lift off quickly the BOV will open rapidly and quickly dispell all the internal pressure with a single woosh sound (plumbed back too). With higher boost levels the chatter gets louder, quicker and the BOV sounds starts to almost make a cracking sounds as it snaps open.

Another RB20 with stock turbo and 14psi had a very loud, long and slow chatter. This is due to the stock wastegate actuator and the bleed type boost controller having poor control over the turbo sytem combined with a large intercooler. The more effecient the system the tighter and quicker the chatter. Have a listen to a rally car some time as it lift's on and off thru a corner.

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as the guy from GFB told me, they used to build turbo cars without BOV's anyway so it can't be that bad....

I agree. The only reason for a blow off valve is to keep the turbo speed up. If there is no blow off valve (or blocked), when the throttle is snapped shut, the turbo is still spinning really fast and producing boost but the compressed air has nowhere to go. This causes backpressure in the turbine and slows it down which in turn means it takes longer for the turbo to spool up again. With a properly fitted and adjusted blow off valve, excess air can be vented (or plumbed back) keeping the turbo speed up and lessening the spool up time.

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for me i dont like the idea of pressurized air hitting a rotating assembly at high speed, even if the compressor blades are tough as nails, specially with a ceramic turbine wheel. Think about it, pressure is forcing air to stop a compressor wheel so suddenly yet, the turbine wheel has to spin cos the exhaust tells it to??

i might b wrong, but oh well

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trbo32 - As one of the 'know it all legends' I accept your apology. lol.

I don't think anyone was having a go at you or patronising you. You were simply corrected.

I accept the apology, I wasn’t trying to cause any rifts I just got a bit pissed at what R31Nismoid said, but it’s cool.

drifto that sounds pretty accurate and close to what I have heard also.

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jeeeeez there's alot of bullshit that get pushed around these forums and not many of us are experts but we all believe we're right.

My theory is delevoped from talking to so called experts and I believe it makes sense.

No.1 The fluttering sound is better termed wastegate chatter! It is there air pressure in the turbo and intercooler system building and escaping thru the internal wastegate of the turbo when a sudden lift of will cause these internal pressures to rise rapidly and open the wastegate at the set level by your boost control.

forgive me... i gotta ask just one question.

If the wastegate (integral or external) is on the exhaust side...

And the build up air/pressure is on the intake side...

Then... How does the pressurized air from the intake side get to the exhaust side without going through the motor because you have lifted of the throttle?

The BOV on a turbo motor is always on the intake side not the exhaust side.

To me that makes no loigical sense at all... unless someone can clarify that whole post for me please.

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Yeah, i always thought flutter was that wonderous sound of compressor surge where the turbo is beight forced in the oposite direction (no actually spinning the other way just chopping the air as the air tries to spin it....(just as owned was describing)...

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