I'm getting the fluttering sound from my bov when I release the throttle under boost. I am boosting up to 10 #s right now on the stock turbo. My old apexi unit fluttered and so does my used blitz unit. I have it hookedup to a vacuum/psi source, and I have played with the spring settings on it to no avail. I have heard the flutter sound before on other stock turbo cars with upgraded bovs. I think its the sound of compressor surge. My old stock bov sounded right.So whats going on?

 

Make sure the vacuum source is behind the throttle plate, when the plates close a vacuum is created which should open the valve, if you have the source before the plates you are providing a boost source to the BOV and all you are doing is holding it closed real well

 

opps. We shall try that.

 

Yea, we shall check that out.