Help on Tuning a BOV please

[99GSTEclipse]

Ok I have a HKS Super Sequential blow off valve on my 99 GST spyder, and i want to know how do i know if its tuned right, because it has a screw on the back, but i dont know what it should be at, when it goes off it makes a the normal screetch and then a fluttering sound. how should i tune it?

 

[L2RTSiAWD]

THe HKS is a very tight BOV to begin with so anything under like 10psi is going to flutter.

 

[rubbersidedown]

the fluttering is the turbo surging because the bov is too tight. right?