Turbo chatter / flutter

[novadose2009]

hi im trying to get some more information about d.v / wastegate flutter. Does this come from a d.v or a wastegate, and does only certain turbos achieve this noise ect.

all information is welcome.

thanks simon

[Spudly]

If im right, usually chatter is the recirculating wastegate sending the unused boost back into the turbo, which then stalls the turbo, the chattering you hear is the turbo stalling and afaik its not conducive for the longevity of the turbo:eek:

[MK999]

2 different things, turbo flutter is the blades stalling against the pressure on the closed TB (i.e no DV fitted). Wastegate chatter is less audible and is the result of the wastegate opening and closing rapidly.

[novadose2009]

Thanks this is what im talking about any information on this corsa would be appriciated also.

http://www.youtube.com/watch?v=cLgtZgIxYho

[Mieran]

If you have a dump valve/bov/recirculating valve when you let of the throttle the boost goes out through one of them depends which one you have.

If you don't have any of the above then it will make the pigeon sound everyone calls 'chatter' becuase boost is pushed back into the turbo.

[novadose2009]

If you have a dump valve/bov/recirculating valve when you let of the throttle the boost goes out through one of them depends which one you have.

If you don't have any of the above then it will make the pigeon sound everyone calls 'chatter' becuase boost is pushed back into the turbo.

In the clip above that corsa is running a d.v straight off the top hat but would it being the turbo using a internal wastegate to make that noise?

thanks for your help.

[Mieran]

Dump valve might be running a strong spring so at low boost levels its not letting air out hence the chatter and it will whoosh at higher boost levels

[novadose2009]

ah i see so if thats the case would that noise then be achievable on any turbo just depending on the boost p.s.i that can be achieved