Powerlab GT35R 8lbs
My TiAL blow off valve sounds exactly like that too, whereas my brother’s PowerLab 350Z has the standard pssshh. As far as I know it has to do with the spring in the bov, I believe there are two springs available through TiAL and depending upon which one you have you’ll either get the flutter sound or the standard pssshh sound.
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From: Davie
8lb spring and also keep in mind ive got open dumps....lol @ traction... i BARELY pushed the car in this video... maybe like up to 4 NO more than 4.5k rpm... im runnin aggressive offsets n STREEEETCH tires (FTL in the performance aspect).. 10.5 rear wit a 0 offset on a 255 FALKEN tire hahahaha... makes the car look awesome though...
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From: Davie
Plus im not loosing any boost... almost holds 8lbs to redline... went off by a lil think to like 7.6 or so...
Been smashing on this car though mayne...
stage II srt 4's mazdaspeed 3's
b16 hatchy on boost
gsr on boost...
eatin em all up
love this car
Been smashing on this car though mayne...
stage II srt 4's mazdaspeed 3's
b16 hatchy on boost
gsr on boost...
eatin em all up
love this car
sounds good!! I get that fluttering from my BOV too.. I dont even have tial though so.. but sounds great man!.. I love seeing e92 M3 owners faces after they get walked by bus lengths loll
Thats compressor surge then. My car did that as well with the stock 10psi BOV spring. Snyper changed his BOV spring all the way to 7psi to fix his PL setup.
Surge has nothing to do with holding boost, has to do with not dumping fast enough. That flutter is most likely your compressor wheel rapidly slowing down from the backpressure in the charge pipes.
A supra doing the same thing
www.youtube.com/watch?v=QjJBVQSvFs8
Surge has nothing to do with holding boost, has to do with not dumping fast enough. That flutter is most likely your compressor wheel rapidly slowing down from the backpressure in the charge pipes.
A supra doing the same thing
www.youtube.com/watch?v=QjJBVQSvFs8
Last edited by str8dum1; Jul 23, 2010 at 09:45 AM.
Thats compressor surge then. My car did that as well with the stock 10psi spring. Snyper changed his BOV spring all the way to 7psi to fix his PL setup.
Surge has nothing to do with holding boost, has to do with not dumping fast enough. That flutter is most likely your compressor wheel rapidly slowing down from the backpressure in the charge pipes.
A supra doing the same thing
www.youtube.com/watch?v=QjJBVQSvFs8
Surge has nothing to do with holding boost, has to do with not dumping fast enough. That flutter is most likely your compressor wheel rapidly slowing down from the backpressure in the charge pipes.
A supra doing the same thing
www.youtube.com/watch?v=QjJBVQSvFs8
If it was compressor surge it would do it even at full boost letting off at 7K. I hear that flutter when im driving around in the city and I give it some gas and let go.. I dont mind the sound. I just dont want it to be surge. ( i dont think it is )
edit : I looked at Chefs, video on his PL setup.. he gets that fluttering also .. ?
Last edited by Vas_Z33; Jul 23, 2010 at 09:49 AM.
At high boost you might not hear it as distinctly, but that doesnt mean its not surging.
Search a few more on youtube. Just sayin it sounds alot like this
www.youtube.com/watch?v=OuNTnA5A2Fo
Search a few more on youtube. Just sayin it sounds alot like this
www.youtube.com/watch?v=OuNTnA5A2Fo
Last edited by str8dum1; Jul 23, 2010 at 09:56 AM.
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From: Davie
Not too sure about the compressor surge but ill research more n ask questions...
U say not dumping fast enough? Not sure if it means anything but im running open dumps...
The car has always sounded like dat from day 1 of install n when taken to my tuner he didn't mention anything... I've heard other bov's n some r like a straight SWOOSH like Alberto's but lots of PL setups I've heard have this flutter sound...
Car runs likea beast n currently not experiencing any problems at all...
Just in case though u said Snyper fixed his flutter by switchin to a 7lb spring? so would that mean id have to run less boost? I hope not... I never planned goin any lower, I jus wanna go higher =)
U say not dumping fast enough? Not sure if it means anything but im running open dumps...
The car has always sounded like dat from day 1 of install n when taken to my tuner he didn't mention anything... I've heard other bov's n some r like a straight SWOOSH like Alberto's but lots of PL setups I've heard have this flutter sound...
Car runs likea beast n currently not experiencing any problems at all...
Just in case though u said Snyper fixed his flutter by switchin to a 7lb spring? so would that mean id have to run less boost? I hope not... I never planned goin any lower, I jus wanna go higher =)
you are confused. I am talking about the spring in your BOV (tial has 3 or 4 pressures), not your wastegate. The wastegate spring is what controls how much boost you run.
By dumping, i mean venting the air out the BOV.
The BOV spring controls how much vacuum it takes to open the BOV. Kinda like adjusting the screw on top of the vortech BPV. YOu essentially have it too tight, so its not opening fast enough to release all the extra charge. The extra charge has to go somewhere, and that's back thru the turbo compressor.
Sure the car will run fine, but it still not good for the turbo or its bearings. Properly setup, it should just be that pshh sound with no flutter.
By dumping, i mean venting the air out the BOV.
The BOV spring controls how much vacuum it takes to open the BOV. Kinda like adjusting the screw on top of the vortech BPV. YOu essentially have it too tight, so its not opening fast enough to release all the extra charge. The extra charge has to go somewhere, and that's back thru the turbo compressor.
Sure the car will run fine, but it still not good for the turbo or its bearings. Properly setup, it should just be that pshh sound with no flutter.
Last edited by str8dum1; Jul 23, 2010 at 10:02 AM.
I read up that some BOVs, make that flutter.. but that deosnt mean its surge right away. as long as it doesnt do it when its building full boost. When you are at partial throttle and the bov flutters.. its harmless. could be wrong.. dunno.
some supras even modify the bov to get that flutter noise. weird
could be wrong.. dunno.some supras even modify the bov to get that flutter noise. weird
If the OP was WOT at 4000 he was under full boost....
In the end it doesnt matter much as the boost levels being run in your cases isnt very high. The cars are running great, so buying different springs to fix the flutter is probably just academic at this point.
In the end it doesnt matter much as the boost levels being run in your cases isnt very high. The cars are running great, so buying different springs to fix the flutter is probably just academic at this point.
I read up that some BOVs, make that flutter.. but that deosnt mean its surge right away. as long as it doesnt do it when its building full boost. When you are at partial throttle and the bov flutters.. its harmless. could be wrong.. dunno.
some supras even modify the bov to get that flutter noise. weird
could be wrong.. dunno.some supras even modify the bov to get that flutter noise. weird
Thats compressor surge then. My car did that as well with the stock 10psi BOV spring. Snyper changed his BOV spring all the way to 7psi to fix his PL setup.
Surge has nothing to do with holding boost, has to do with not dumping fast enough. That flutter is most likely your compressor wheel rapidly slowing down from the backpressure in the charge pipes.
A supra doing the same thing
www.youtube.com/watch?v=QjJBVQSvFs8
Surge has nothing to do with holding boost, has to do with not dumping fast enough. That flutter is most likely your compressor wheel rapidly slowing down from the backpressure in the charge pipes.
A supra doing the same thing
www.youtube.com/watch?v=QjJBVQSvFs8
Flutter isnt necesarly end of the world bad compressor surge though. Technically flutter only occurs with a BOV, and surge is with turbo... but that is more semantics than anything.
All fluttering noise isn't bad, as long as it goes away and has a changing frequency, as that is the BOV piston fluttering open and it’s like a ball bouncing, how the frequency gets higher and higher until it stops, and it’s more of a whistling sound.
Instead of gravity pulling on the ball, and the ball having less and less energy, bouncing lower and lower until it stops. The BOV flutter is blowing off some air, and less and less air is released until it stops.
It's basically from too tight of a spring. The air starts to get out, and then the pressure drops too low to compress the spring and keep the BOV open so it shuts, then the pressure builds again, so same process, it just doesn't open as long (why the sounds gets higher pitched), like I explained with the ball and gravity.
Some call it the turkey gobble or the pigeon call or flutter dump, its ok, and won't harm anything, you just have too tight of a spring. You can loosen it if you want to be rid of the sound, but you might have trouble holding higher boost. Here is a great video and you can actually watch the BOV flutter 9 secs in a correlate the "ball bouncing sound" as the BOV increases its frequency and higher pitch, and finally stops.
http://www.youtube.com/watch?v=Ffj01...layer_embedded
There are plenty of similar examples with the HKS SSQV
What IS bad is when the flutter is metallic, generally higher pitched to begin with and continuous, without change, as that compressor blade 'smacking' against the air and is generally a higher frequency as the compressor blade is spinning fast. This is bad for your turbo. It is much like too high of a back pressure, it never actually has the blades moving the other way, and it just puts a ton of strain on the bearings and shaft. There is no, less and less air or and slowing down (ball bouncing effect), it’s a constant frequency beating of the blades.
http://www.youtube.com/watch?v=MU5Y6...layer_embedded
This is also compressor surge, as you can see the BOV not even open and you hear the surging
http://www.youtube.com/watch?v=gvnBD...layer_embedded
you really start to hear it @ 1:04. And the fluttering sound is constant not "bouncing down", and not as 'whistly' as a flutterdump.
But what is terrible to hear is when you are under load and you get flutter. like this vid.
http://www.youtube.com/watch?v=nCj6S...layer_embedded
If you are ever WOT and you hear a flutter, THAT, is VERY BAD. It doesn't even have to do with a BOV, as your BOV should be shut during boost, so how is a BOV causing a surge? It means your A/R is too small for the boost you are running (very unlikely as you engine will most likely blow up before this from the hot air), but most likely, your had some dirt or something that over time rounded off/clipped your compressor blade and the 'seal' (blade tip to housing clearance/tolerance) isn't as good and the blade beats/slaps the air vs., pushing it. Like if you cut the compressor blade in half, it would give you a little bit of boost at first, but then it would lose efficiency VERY fast and then it would slap the air, vs. compress and push it. It is not that 'bad' for your engine or turbo... as you turbo is already F'd lol. So it is bad news, and not good to hear, but you’re not damaging anything when you hear flutter/surge under WOT.
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From: Davie
Like a lot of thing i tried to talk to him he just didnt want to hear me just as probably he still thinks he never got a gt37r. Yes a simple spring should fix the "minimal" (imo) issue related to this, but usually the point is that stronger spring is shipped to be ready to hold higher boost...anyways...
Flutter isnt necesarly end of the world bad compressor surge though. Technically flutter only occurs with a BOV, and surge is with turbo... but that is more semantics than anything.
All fluttering noise isn't bad, as long as it goes away and has a changing frequency, as that is the BOV piston fluttering open and it’s like a ball bouncing, how the frequency gets higher and higher until it stops, and it’s more of a whistling sound.
Instead of gravity pulling on the ball, and the ball having less and less energy, bouncing lower and lower until it stops. The BOV flutter is blowing off some air, and less and less air is released until it stops.
It's basically from too tight of a spring. The air starts to get out, and then the pressure drops too low to compress the spring and keep the BOV open so it shuts, then the pressure builds again, so same process, it just doesn't open as long (why the sounds gets higher pitched), like I explained with the ball and gravity.
Some call it the turkey gobble or the pigeon call or flutter dump, its ok, and won't harm anything, you just have too tight of a spring. You can loosen it if you want to be rid of the sound, but you might have trouble holding higher boost. Here is a great video and you can actually watch the BOV flutter 9 secs in a correlate the "ball bouncing sound" as the BOV increases its frequency and higher pitch, and finally stops.
http://www.youtube.com/watch?v=Ffj01...layer_embedded
There are plenty of similar examples with the HKS SSQV
What IS bad is when the flutter is metallic, generally higher pitched to begin with and continuous, without change, as that compressor blade 'smacking' against the air and is generally a higher frequency as the compressor blade is spinning fast. This is bad for your turbo. It is much like too high of a back pressure, it never actually has the blades moving the other way, and it just puts a ton of strain on the bearings and shaft. There is no, less and less air or and slowing down (ball bouncing effect), it’s a constant frequency beating of the blades.
http://www.youtube.com/watch?v=MU5Y6...layer_embedded
This is also compressor surge, as you can see the BOV not even open and you hear the surging
http://www.youtube.com/watch?v=gvnBD...layer_embedded
you really start to hear it @ 1:04. And the fluttering sound is constant not "bouncing down", and not as 'whistly' as a flutterdump.
But what is terrible to hear is when you are under load and you get flutter. like this vid.
http://www.youtube.com/watch?v=nCj6S...layer_embedded
If you are ever WOT and you hear a flutter, THAT, is VERY BAD. It doesn't even have to do with a BOV, as your BOV should be shut during boost, so how is a BOV causing a surge? It means your A/R is too small for the boost you are running (very unlikely as you engine will most likely blow up before this from the hot air), but most likely, your had some dirt or something that over time rounded off/clipped your compressor blade and the 'seal' (blade tip to housing clearance/tolerance) isn't as good and the blade beats/slaps the air vs., pushing it. Like if you cut the compressor blade in half, it would give you a little bit of boost at first, but then it would lose efficiency VERY fast and then it would slap the air, vs. compress and push it. It is not that 'bad' for your engine or turbo... as you turbo is already F'd lol. So it is bad news, and not good to hear, but you’re not damaging anything when you hear flutter/surge under WOT.
Flutter isnt necesarly end of the world bad compressor surge though. Technically flutter only occurs with a BOV, and surge is with turbo... but that is more semantics than anything.
All fluttering noise isn't bad, as long as it goes away and has a changing frequency, as that is the BOV piston fluttering open and it’s like a ball bouncing, how the frequency gets higher and higher until it stops, and it’s more of a whistling sound.
Instead of gravity pulling on the ball, and the ball having less and less energy, bouncing lower and lower until it stops. The BOV flutter is blowing off some air, and less and less air is released until it stops.
It's basically from too tight of a spring. The air starts to get out, and then the pressure drops too low to compress the spring and keep the BOV open so it shuts, then the pressure builds again, so same process, it just doesn't open as long (why the sounds gets higher pitched), like I explained with the ball and gravity.
Some call it the turkey gobble or the pigeon call or flutter dump, its ok, and won't harm anything, you just have too tight of a spring. You can loosen it if you want to be rid of the sound, but you might have trouble holding higher boost. Here is a great video and you can actually watch the BOV flutter 9 secs in a correlate the "ball bouncing sound" as the BOV increases its frequency and higher pitch, and finally stops.
http://www.youtube.com/watch?v=Ffj01...layer_embedded
There are plenty of similar examples with the HKS SSQV
What IS bad is when the flutter is metallic, generally higher pitched to begin with and continuous, without change, as that compressor blade 'smacking' against the air and is generally a higher frequency as the compressor blade is spinning fast. This is bad for your turbo. It is much like too high of a back pressure, it never actually has the blades moving the other way, and it just puts a ton of strain on the bearings and shaft. There is no, less and less air or and slowing down (ball bouncing effect), it’s a constant frequency beating of the blades.
http://www.youtube.com/watch?v=MU5Y6...layer_embedded
This is also compressor surge, as you can see the BOV not even open and you hear the surging
http://www.youtube.com/watch?v=gvnBD...layer_embedded
you really start to hear it @ 1:04. And the fluttering sound is constant not "bouncing down", and not as 'whistly' as a flutterdump.
But what is terrible to hear is when you are under load and you get flutter. like this vid.
http://www.youtube.com/watch?v=nCj6S...layer_embedded
If you are ever WOT and you hear a flutter, THAT, is VERY BAD. It doesn't even have to do with a BOV, as your BOV should be shut during boost, so how is a BOV causing a surge? It means your A/R is too small for the boost you are running (very unlikely as you engine will most likely blow up before this from the hot air), but most likely, your had some dirt or something that over time rounded off/clipped your compressor blade and the 'seal' (blade tip to housing clearance/tolerance) isn't as good and the blade beats/slaps the air vs., pushing it. Like if you cut the compressor blade in half, it would give you a little bit of boost at first, but then it would lose efficiency VERY fast and then it would slap the air, vs. compress and push it. It is not that 'bad' for your engine or turbo... as you turbo is already F'd lol. So it is bad news, and not good to hear, but you’re not damaging anything when you hear flutter/surge under WOT.
hah yah...not you of course maing . we are cool and i didnt mean to be offensive in my reply... it was to a line on rich(str8)s post...but not much on topic about the flutter so i didnt wanna go much off a tangent ... i should have been clearer
and i didnt mean to be offensive in my reply... it was to a line on rich(str8)s post...but not much on topic about the flutter so i didnt wanna go much off a tangent ... i should have been clearer
quick, i'm going to pm you. I'm running a light spring recommended by tial due to my low vac at idle. I'm going to be running high boost with my 6765 and you mentioned a light spring won't hold boost. i'm curious why.
If you thing about the way a Tial BOV works it will make sense. The top of the BOV is connected to the manifold, so whtever the boost pressure is, the BOV will see the same + spring.
It is not possible for the valve to open.