Install ? For those with BOVs

[Dennis F]

Interesting, I would think you would want the valve closed at idle. The only time it should open is when you let off the throttle, positive pressure in the UICP puts force on the bottom of the valve, while the greater vacuum helps pull the valve up.

All good info, thanks.

 

[wiseman]

Yes, you do want the valve closed at idle b/c the valve is located after the MAF , which the air that passes into the phlenom has been metered. So, from the previous post, the 9lb spring (with no washers) allowed the BOV.to fluctuate open and closed at idle (not correct for a GN). Once the washers were added to the 9lb spring, it stiffened the force of the spring and the valve did not fluctuate at idle anymore, but still opened correctly under boost once my foot got off the petal and the throttle blade closed and vacuum pulls it back closed.