air passage through blow off valve

[1mean4.3]

I just installed my HKS SSQV and I can feel air passing through it at all times, during idle, with throttle, etc. Is this normal? I have it Tee'd into my vacuum line correctly and it was my understanding that it would only release air under built up pressure after I let off the gas. I'm afraid it going to cause me to lose boost. This is on a supercharger if it matters.

Thanks for any input.

 

[SY2932]

Re: air passage through blow off valve

Did you install the check valve correctly and did you adjust the diaphragm on the back?

 

[1mean4.3]

Re: air passage through blow off valve

No on the diaphragm, I'll give that a look tonight and go from there. Thanks!

 

[jharrison]

Re: air passage through blow off valve

Correct me if im wrong, but the line from the intake to the BOV shouldn't have a check valve. Most BOV kits include a filter that look similar to a check valve. If the check valve is installed, the BOV will only see vacuum and never boost, therefore, never work correctly.

 

[turbomatt]

Re: air passage through blow off valve

yeah, a BOV needs a boost/vac source to work properly. boost + spring pressure on the diaphragm hold it shut and a sudden spike in vacuum on the diaphragm plus positive pressure on the charge air pipe side forces it open.. if no boost is present all you have is a soft spring holding it shut which = major boost leak. so that's a no on the check valve. sucking/blowing at idle means you need to tighten the adjustment screw on the back JUST tight enough to hold it shut at idle. too tight = surge and slow response. :2cents:

 

[typhoon fever]

Re: air passage through blow off valve

the hks ssqv doesn't have any adjustments on it. if it doesn't seal its broken or the line isn't hooked up rite. i ran mine to the line that comes out of the front of the upper intake.

 

[turbomatt]

Re: air passage through blow off valve

i had a ssqv on my boosted 240sx and it had a adjustment on the back. i think the new models may not but i haven't purchased a bov since then.