The spring pressures in a BOV have nothing to do with the amount of boost you plan on running, the spring pressure relates to the pressure differential at which the valve opens, You can run a BOV with a 7 pound spring to 100psi if you want. The different rate springs are for sizing for vaccum sources. In other words a v8 with a single throttle body draws a lot more vacuum then a vacuum nipple from a single throttle body on a 4 cylinder bike.(xcitebike @ Sep. 19 2006,15:04) Thanks guys, I just asked a friend if he could look into the tial blowoff valves and find the quietest version he has.
Unfortunately most of his come in 7lbs or 11lbs for spring pressure.
Ill have to get one with a beefier spring for the occasional burst to 15 pounds.
I have always hated the advertisement of forced induction.
Blowers should be whisper quiet and blow offs should be as well.
Walk softly and carry a big stick.