Flutter dump

[senna]

Holy shit, 3 pages on "flutter"
Only OzHonda.

If it's that much of a concern then:
http://i123.photobucket.com/albums/o...8/IMG_0053.jpg

http://carphotos.cardomain.com/ride_...0009_large.jpg

I assume that because you linked pics of turbos with surge slot covers you are mistaken by what we are talking about being compressor surge, the flutter sound being discussed could be described as one form of compressor surge.

Compressor surge is when the turbo is being pushed past its normal operating RPM and it starts to "chop" the intake air and not pump it efficiently. The slots in the compressor housing allow turbulence to be created before the compressor wheel which in turn slows the intake air speed and allows the turbo to run efficiently.

Compressor surge can also happen when the motor cannot accept or i guess you could say "ingest" the amount of air the turbo is sending it. This results in the charge air "backing up" in the hotside pipes back to the compressor wheel which can cause a noise that kind of sounds like a half open blow off valve...

[nigs]

Are you saying it doesn't aid in the reduction of said "flutter" at all?

[mugen_ctr]

Are you saying it doesn't aid in the reduction of said "flutter" at all?

It aids in the reduction of compressor surge, there are few ways to combat compressor surge

What many say an hear is common compressor surge as they dont wanna use BOV or have BOV set to open at set level boost... When u start talking about turbo compressor surge, as in what senna has described, its a different thing... especially when ur chasing power, its the last thing u want to happen... really robs u of power... though ive never really experience it as bad as the youtube link, any form of compressor surge to the turbo isnt what u want as it creates a form of unstable air flow, hence why ALL manufactures equip there cars with recirculating bov

[nigs]

Didn't answer my question.

Are you saying it does nothing for "flutter" ?

[mugen_ctr]

Didn't answer my question.

Are you saying it does nothing for "flutter" ?

LOL... Flutter = Compressor surge... So yessss, having that type of compressor housing, or anti surge housing will remove it... BUT as ive said, having no BOV to induce compressor surge isnt ideal, but having compressor surge occurring whilst driving is much much worse...

IF u dont want compressor surge because u didnt have a bov on, whack on a OEM Skyline GTR bov, and plumb it back into the turbo intake..... why? because OEM cars dont have any form of compressor surge

[nigs]

Yeah, regardless of what the primary purpose of those compressor housing are.
So no, I was not mistaken into thinking "flutter" was compressor surge. The 2 are different but the ported housings can be applied to both.

I never implied or suggested "flutter" was surge or otherwise.

[XB-16-AX]

[senna]

Didn't answer my question.

Are you saying it does nothing for "flutter" ?

I'm saying that the flutter the guys are talking about has more to do with BOV selection and not turbo housing design or wastegates.

Surge slot cover equipped turbos will still suffer from this flutter since compressed air is still pushing against the compressor, or more specifically the exducer blades.

Namsayin...lol

[trism]

And this is where all the confusion comes in.

The term "compressor surge" must be used exclusively for what we see in the video of the R33 above.

The lack of BOV resulting in the typical sound when you get off the throttle is called flutter or dose. It has never been called, and never shall be called "compressor surge"

[EKVTIR-T]

And this is where all the confusion comes in.

The term "compressor surge" must be used exclusively for what we see in the video of the R33 above.

The lack of BOV resulting in the typical sound when you get off the throttle is called flutter or dose. It has never been called, and never shall be called "compressor surge"

So what is actually producing the flutter sound?

[mugen_ctr]

And this is where all the confusion comes in.

The term "compressor surge" must be used exclusively for what we see in the video of the R33 above.

The lack of BOV resulting in the typical sound when you get off the throttle is called flutter or dose. It has never been called, and never shall be called "compressor surge"

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

[trism]

So what is actually producing the flutter sound?

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.