Turbo Flutter?

[Shaky Bones]

if it is indeed compressor surge. (Making the fluttering sound after taking your foot off the accelerator)

the problem you have Flow from whatever bov you have.

it is basically the sound of the compressed air bouncing back and forth between the turbo and now closed throttle body with no where to go. It is NOT the sound of the turbo blades 'cutting the air' which many people will tell you.

Look the easiest way of solving this problem is strap on a big ass atmospheric BOV. Something like a Turbosmart Megasonic, Those bastards can flow over 800hp. and will make a incredible "PSCHHHHHHHH" sound on back off. But alas are illegal.

You really need to stay legal a high flowing plum back BOV, Im sure the guys on here can recommend something. Personally I like the GFB Stealth FX, but am not sure it will flow enough air for your application.

anyway it all depends on how loud the fluttering is, if it is not all that loud you wont be doing much damage to your turbo if any at all. if it is loud then maybe a new bov is needed