Has anyone actually had any bad expeirences from not using a BOV filter? i was wondering if i should even bother picking one up for my drag3 kit

 

anyone know?

 

i havent seen many used, but thats really not any help.

 

Why would you need a filter on a BOV when all it does is expel excess air?

 

I would not worry about it. A filter is not really needed on a BOV. It only works during a pressure differential resulting in air flow out of the system.

 

i belive it works during vacumm, some bov come with them

 

mine opens up alot during idle, I've worried about this also.

Nick

 

what bov do you have?

blitz have an option for one.. i have hks.. so i dont really know how to go about filter.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vtec.dc2 &raquo;</TD></TR><TR><TD CLASS="quote">what bov do you have?

blitz have an option for one.. i have hks.. so i dont really know how to go about filter.</TD></TR></TABLE>

The SSQV BOV comes with filter also... I used to have it on my old turbo setup... It comes in the box and looks like a check valve, one side is yellow and the other is black I believe... It goes on the vaccumm line in between the manifold and BOV...

 

i bet like 80 percent of the ppl dont put a filter on there bov.

 

BOV's do open when under a vacuum load from the manifold/engine. Once the car is producing boost the valve shuts and closes the system untill the throttle plate closes and then the car goes into vacuum, once again opening up the BOV and allowing it to vent excess charge pressure. Put a filter on it, or better yet recirculate the air back into the intake part of the system but before the turbo inlet.

 

in that case.. isn't that the same as putting a filter on vacuum lines if you didn't have a turbo? maybe i don't fully understand, but i don't see the need for filter on vacuum line.

 

why would you need to filter already filtered air?

 

you're not putting a filter on a vacuum line, you're putting it on the BOV because air goes both in and out of it. When the car is in vacuum (not making boost) the signal opens the BOV because the BOV has a vacuum/boost signal going to it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Butcher &raquo;</TD></TR><TR><TD CLASS="quote">you're not putting a filter on a vacuum line, you're putting it on the BOV because air goes both in and out of it. When the car is in vacuum (not making boost) the signal opens the BOV because the BOV has a vacuum/boost signal going to it. </TD></TR></TABLE>

maybe im stupid but i dont understand how air goes into the bov. in vacuum, the bov is opend by vacuum, but is there actually amounts of air sucked from the bov through the vacuum line into the intake manifold? enough to need a dinky filter? i was assuming the thread was about that filter that goes on the vacuum line. ive never seen or actually heard of anyone putting a filter ON the bov.

 

the BOV in vacuum is just like one big vacuum leak, sure air is drawn into it. Drill a hole in your pipe and you will get the same effect, air will go into it. The engine by nature creates a vacuum inside the cylinder and that vacuum (low pressure) is what draws air into the motor. Now if you have holes in your intake plumbing before the throttlebody, then yes air will enter the system anywhere it can. When the turbo is producing boost, the engine is not creating vacuum any longer, the BOV shuts, and all is happy. Here is a picture for you visual learners Where the filter is is where air goes into/out of!

 

hks owners run a check valve on the vac line so it only sees boost. therefore air only goes out. otherwise.... oh well.no filter, no big deal.

 

does the check valve change the response of a BOV at all? anyone done this on another type of vlave?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by thad &raquo;</TD></TR><TR><TD CLASS="quote">hks owners run a check valve on the vac line so it only sees boost. therefore air only goes out. otherwise.... oh well.no filter, no big deal.</TD></TR></TABLE>

then how does the BOV open? if it never sees vacuum, and vacuum is what opens the valve, then the valve is not opening..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by filthy scarecrow &raquo;</TD></TR><TR><TD CLASS="quote">

then how does the BOV open? if it never sees vacuum, and vacuum is what opens the valve, then the valve is not opening..

</TD></TR></TABLE>

The BOV opens when it sees boost... That's what it's supposed to relieve... When it's open during vacuum, it draws slight amounts of air in, thus the "check valve" style filter in the vacuum line to prevent unfiltered air into the manifold... (On HKS SSQV)

 

the BOV does not open when it sees boost, that is the duty of the wastegate. The BOV is strictly a pressure relief valve for when the throttle closes.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Butcher &raquo;</TD></TR><TR><TD CLASS="quote">the BOV does not open when it sees boost, that is the duty of the wastegate. The BOV is strictly a pressure relief valve for when the throttle closes.</TD></TR></TABLE>


And when the throttle closes, what does it relieve...? What comes out...? That's why you can't BOV with vacuum... Yes, you can blow off before the boost gauge actually reads a pound of boost, but that is because the turbo is building boost, thus the need to relieve it... If what you're saying is true, do know how many ricers would be running around with AEM CAI with BOV's retrofitted...

 

If a BOV opened when it saw boost, you would never hold a charge. The BOV opens when it sees vacuum and relieves the boost in the system. Why do you think you hook the BOV up to a vacuum source.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Butcher &raquo;</TD></TR><TR><TD CLASS="quote">If a BOV opened when it saw boost, you would never hold a charge. The BOV opens when it sees vacuum and relieves the boost in the system. Why do you think you hook the BOV up to a vacuum source.</TD></TR></TABLE>

i agree

 

to explain a bit further, the BOV really opens when pressure in the intake piping exceeds the pressure in the manifold