Bov question.
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From: Taos, New mexico
Well my bov sounds like it cant blow off all the air at once. Kind of a fluttering noise... I was thinking since only 5 psi of air is escaping perhaps its not fully opening the valve?
Is this normal for my bov, or is there something i can do to make it make more of a "whoosh" sound?
Because everyone knows the louder and more "whooshy" your bov sounds, the bigger your ***** is.
Is this normal for my bov, or is there something i can do to make it make more of a "whoosh" sound?
Because everyone knows the louder and more "whooshy" your bov sounds, the bigger your ***** is.
open the BOV and take out the softer of the two springs, try again. I again no luck, try just using the softer of the two, and try full in and out adjustment.
http://www.evomoto.com/tech_info.php?tPath=1&tech_id=7
http://www.evomoto.com/tech_info.php?tPath=1&tech_id=7
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From: Tucson "it's 110º" Arizona
Here are some directions to get that BOV adjusted properly. Pull the valve off the I/C pipe, grap your allen wrench set, follow the instructions on the one spring mod posted by B-Money, (while it's apart) loosen the adjustment stud, re-assemble, attach to pipe/vacuum source. Test.
IMO: The "one spring mod" Braineack posted is a good idea, I've done it to my Type-S. With the larger spring, the valve starts to "leak" at 15 PSI.
Let the ***** enlargement commence..
Joined: Jun 2005
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From: Fake Virginia
does the type S have two ports? if it DOES....

run the top port to the manifold and run the bottom port to somewhere upstream of the throttle body.
that way when the throttle closes on boost, the bottom port will push up on the diaphragm while the top port sucks it up.... double the force on the diaphragm!
then when the throttle is open on boost, it'll stay closed with the spring since both ports have boost.
and when you're in vac, same thing.
if it's hooked that way, it wont ever leak and you can use the spring as it was intended.
Matt

run the top port to the manifold and run the bottom port to somewhere upstream of the throttle body.
that way when the throttle closes on boost, the bottom port will push up on the diaphragm while the top port sucks it up.... double the force on the diaphragm!
then when the throttle is open on boost, it'll stay closed with the spring since both ports have boost.
and when you're in vac, same thing.
if it's hooked that way, it wont ever leak and you can use the spring as it was intended.
Matt
Last edited by y8s; Feb 12, 2007 at 12:50 PM. Reason: called the bottom the top and the top the bottom duh.
Thread Starter
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From: Taos, New mexico
Hmmmm, well i got mine to sound ******* amazing. Huge loud WHOOOOSH, loving it.
It was all because im an idiot, but thats ok. I found out about the actual allen adjustment on the top when i took it apart, and i realized... "no ****, that nut doesnt do anything but lock the other bolt in place" (i thought the nut on the outside was the adjuster, man im stupid) Then i came back here to read UofACATS post and i felt even more dumb, haha.
Oh well, i used both springs and got it adjusted to blow off at about 2psi+ and still no leaks at idle, or after revs.
Brain, let me know if plugging that other outlet upstream makes any difference.
It was all because im an idiot, but thats ok. I found out about the actual allen adjustment on the top when i took it apart, and i realized... "no ****, that nut doesnt do anything but lock the other bolt in place" (i thought the nut on the outside was the adjuster, man im stupid) Then i came back here to read UofACATS post and i felt even more dumb, haha.
Oh well, i used both springs and got it adjusted to blow off at about 2psi+ and still no leaks at idle, or after revs.
Brain, let me know if plugging that other outlet upstream makes any difference.
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From: Chicago. (The less-murder part.)
I could be way off, never used a Greddy BOV, but I'm thinking about buying one of the cheap eBay knock-offs to try in place of my FM BOV which has been giving me trouble. (I can't keep the piston lubricated for more than a few weeks before it starts sticking again...)
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From: Fake Virginia
Are you sure that's not backwards? Seems like the lower port would go to the intake pipes upstream of the TB, and the upper port would go to the manifold. So pressure (from the pipes) is acting upon the bottom of the diaphragm, and vacuum (from inside the manifold) is acting upon the top of the diaphragm.
I could be way off, never used a Greddy BOV, but I'm thinking about buying one of the cheap eBay knock-offs to try in place of my FM BOV which has been giving me trouble. (I can't keep the piston lubricated for more than a few weeks before it starts sticking again...)
I could be way off, never used a Greddy BOV, but I'm thinking about buying one of the cheap eBay knock-offs to try in place of my FM BOV which has been giving me trouble. (I can't keep the piston lubricated for more than a few weeks before it starts sticking again...)
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