Flutter dump

[trism]

disagree here, there all just nick names for the same thing "compressor surge", so does GFB and few other BOV manufactures... dose/flutter same thing as compressor surge, its been explained previously....

http://gfb.com.au/images/stories/dow...essorsurge.pdf

Yeah, and they're doing nothing to help the confusion. As we already know, there is a very distinct difference between "compressor surge" at full throttle, full boost, and flutter/dose when you are getting off the throttle.

[XB-16-AX]

Are you talking about the flutter when you get off the throttle?

I explained it earlier in this thread.

Rather than going out the BOV, it rushes back at the turbo, because it has nowhere to go since the throttle plate shut, where it gets chopped up and makes that noise.

i think i mentioned this earlier in my posts.. Well something along the lines of compressed air or wasted air going back to the turbo if the BOV is too tight which will cause this flutter via the wastegate/screamer pipe.


Simple: if u dont like the flutter bov sound then buy a plumpback bov.

But if u like shitloads of noise then buy a trumpet bov and add a screamer pipe for the extra noise.

Bear in mind that if the spring on the bov is too tight then u will experience a flutter sound rather than a loudass whooosh...

Nomsayin?

[EKVTIR-T]

Its not via the wastegate/screamer at all.

The flutter is produced from the throttle closing causing a pressure wave against the compressor blades and sounding out via the intake pipe

Axi-symmetric stall, more commonly known as compressor surge; or pressure surge, is a complete breakdown in compression resulting in a reversal of flow and the violent expulsion of previously compressed air out through the engine intake, due to the compressor's inability to continue working against the already-compressed air behind it.

[trism]

[/b]


i think i mentioned this earlier in my posts.. Well something along the lines of compressed air or wasted air going back to the turbo if the BOV is too tight which will cause this flutter via the wastegate/screamer pipe.


Simple: if u dont like the flutter bov sound then buy a plumpback bov.

But if u like shitloads of noise then buy a trumpet bov and add a screamer pipe for the extra noise.

Bear in mind that if the spring on the bov is too tight then u will experience a flutter sound rather than a loudass whooosh...

Nomsayin?

Nope, I don't know what you're saying, because its incorrect.

The waste gate is on the exhaust side. The flutter/compressor surge comes from the intake side.

They are totally unrelated.

[XB-16-AX]

Its not via the wastegate/screamer at all.

The flutter is produced from the throttle closing causing a pressure wave against the compressor blades and sounding out via the intake pipe

Flutter can occur in two ways.

1) slight throttle response then release. The hot pressurised air from the turb -> passing the IC -> cold air to the TB. If the throttle was eased off whilst air was travelling then this cold air should release gently out of the BOV causing a flutter as the boost levels are low.- not enuf to fully open or release air to the bov.

2) the other flutter is same as above but before the hot air reaches the IC. This hot pressurised air will travel back to the Turbo compressor which will then in turn cause the wastegate (internal) to open/close releasing this hot air out to the dump pipe.

In an external gated scenarios - the pressurised air will be released out via screamer pipe.

Yet again, this will depend on how much boost you are running before you decide to ease off the throttle pedalstool.


The reason why u can hear the flutter noise from the filter is because the air is pressurised and is chain of parts that works together.

If u get a 2nd person to listen for a flutter noise from the IC - u will notice and hear that same flutter from all the above locations simultaneously. Try it.


Tru story mun.

Its logical man.

[XB-16-AX]

Nope, I don't know what you're saying, because its incorrect.

The waste gate is on the exhaust side. The flutter/compressor surge comes from the intake side.

They are totally unrelated.

My response on other post.

Flutter occurs both in exhaust housing and compressor (intake) pressurised air.

Turbos work all in unison - its a chain of pressured air that increases output power. All has to work together not just 1 side of the hot vs cold pressured air.


Nomsayin

[senna]

OK, i don't think you are getting it.



See in the picture how the air does not flow through the turbo from inlet to exhaust?

The screamer pipe is attached to the external wastegate, which is generally mounted to the exhaust manifold or the turbine housing of the turbo.





The wastegate only opens when the desired boost level is achieved and the exhaust gas is bled off away from the turbine housing. This is why in the Video i posted last night you here the screamer pipe as the car comes on to boost.

Again, a screamer pipe has nothing to do with flutter.

[trism]

Flutter can occur in two ways.

1) slight throttle response then release. The hot pressurised air from the turb -> passing the IC -> cold air to the TB. If the throttle was eased off whilst air was travelling then this cold air should release gently out of the BOV causing a flutter as the boost levels are low.- not enuf to fully open or release air to the bov.

2) the other flutter is same as above but before the hot air reaches the IC. This hot pressurised air will travel back to the Turbo compressor which will then in turn cause the wastegate (internal) to open/close releasing this hot air out to the dump pipe.

In an external gated scenarios - the pressurised air will be released out via screamer pipe.

Yet again, this will depend on how much boost you are running before you decide to ease off the throttle pedalstool.


The reason why u can hear the flutter noise from the filter is because the air is pressurised and is chain of parts that works together.

If u get a 2nd person to listen for a flutter noise from the IC - u will notice and hear that same flutter from all the above locations simultaneously. Try it.


Tru story mun.

Its logical man.

LOLOLOLOLOLOLOLOLOLOOLOLKOKLKOLLLLLLOLOLOLOLOLOLLO OL

Seriously dude. You've got the completely wrong idea about how turbos work.

[XB-16-AX]

if i can only draw what im trying to say/explain ... LOL.

ive learned information info here guys. thnx

all good were all entitled to opinions and comments.

[trism]

but that's the thing dude.

You're trying to say that the air charge goes out the waste gate dump pipe. But it doesn't. It doesn't go anywhere near it.

[XB-16-AX]

but that's the thing dude.

You're trying to say that the air charge goes out the waste gate dump pipe. But it doesn't. It doesn't go anywhere near it.

ill try to explain it here and my editted dodgy pic.. lol

i know there is no way that the air can travel between the comp wheel to the exhaust wheel (internal gated release valve). (CIRCLED IN RED)

im talking about the unused pressured air marked in Orange box which relates to my example before (2) air filter..

then the yellow box relates to my example (1) (BOV - green circle)



its ok mun, your prob right .. i could be getting all confused from being in the turbo scene for 10+ yrs and have owned/build high powered turbos.

juzz sayin

[trism]

OK. I understand what you're talking about. Some of the air goes out the BOV and some goes back through the compressor wheel, making the flutter noise.


But you are using the term waste gate and screamer pipe when they have nothing to do what we are talking about.

Also, don't try and fxuking big note yourself and talk about how long you've been in the scene.

I know xunts that have been in the modified car scene for 30 years and still don't understand shit. It's all right not to know everything, you've just gotta admit it