My greddy type S has an adjusting knob on top. The main thread has an allen key top and is screwed thru a 10mm (i think) nut.

How do i adjust this thing? There are directional arrows that say 'hard' and 'soft.' i want it softer, but dont know whether to turn bolt, nut or both... Also, does this adjustment ONLY affect the sound, or does it affect the way the BOV performs?

 

Loosen the 10mm nut then turn the allen screw to the loose direction then tighten the nut.

Start off hard then loosen to soft. Test the BOV below vtec. If it's too hard it will not make any noise. When it's close to the right spring tension it will sound like a choking turkey... make small adjustments after that and you will get it where it supposed to be.

If it's a SC application it will vent at idle....and will go WHOOOPIIIIISH when you shift.....

Tim

 

Thanks tim, does this affect the performance/function of the BOV, or just the sound?

 

Both... you don't want the BOV/bypass valve too tight that it does not let it vent at idle or cruising. Because the SC belt is attached to the crank it will continue to be under load thus creating a small of boost that is released out the bypass/BOV.

Once you goose it... the amount of boost will be more than the bypass/bov vaccum pressure and it will close immediately until you release the throttle.

 

ic ic. thanks!!