Greddy type R BOV adjustment

[HCR32]

Hey guys a mate of mine came past my house last night with his r33, hes got a type R greddy bov. Now with his bov when you accelerate and release the pedal it doesnt release the excess pressure. well it does but alittle bit.

All hoses have been checked and everything appears to be in working order.

Im thinking maybe the tension on the bov is set to hard/tight.

Now i was looking at this monsta of a bov and wanted to ask to i adjust the tension via the screw on the top or do i spin the chrome top half clockwise/anti clockwise..

thanks

-B :bananaman