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Shoot me!
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My buddy just got a knockoff Greddy Typs S BOV I have a RS and it only has one vaccumm port going to it so i ran it to the intake manifold. My ? is his has 2 vaccumm ports one at the top and the other in the middle does anyone know or have one of these that knows how to run the vaccumm lines.
 

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you only need to run the top line. the bottom line is for assisting in high boost applications where the one line might not have enough pressure to keep the bov valve seated.
 

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The Master Fabricator
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stackz said:
you only need to run the top line. the bottom line is for assisting in high boost applications where the one line might not have enough pressure to keep the bov valve seated.
:TU:

That's how my type s is hooked up.
 

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whatthehell1051 said:
the knockoffs have vaccum but the originals don't, plug it.
I put a plug on the bottom smaller one. Took the big spring out of it and left the little one in you really have to fuck with it to get to work decent. It sounds great but its hard to stay close at idle air just shoots out of it. I almost have to crank the thing down tight and then it sounds like shit.
 

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The bottom one is actually for positive pressure, you don't hook a vacuum line to it, you hook a boost line to it. It's under the diaphragm, when both are hooked up, it creates no positive pressure on top, the only thing to hold it down now is the spring, it's purpose is to open the valve quicker for low boost applications.
 
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O 16581 72452 5 said:
The bottom one is actually for positive pressure, you don't hook a vacuum line to it, you hook a boost line to it. It's under the diaphragm, when both are hooked up, it creates no positive pressure on top, the only thing to hold it down now is the spring, it's purpose is to open the valve quicker for low boost applications.
actually its for higher boost and hell hatch the bov should be alittle open at idle because when you let off the gas it helps open the valve quicker. the boost the goes through the line helps close it under boost along with the spring. so alittle open at idle is good.
 

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Good thread. I just got my Type S and was wondering where to hook up the bottom nipple too as well. Now I know I don't need to :TU:
 

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whatthehell1051 said:
actually its for higher boost and hell hatch the bov should be alittle open at idle because when you let off the gas it helps open the valve quicker. the boost the goes through the line helps close it under boost along with the spring. so alittle open at idle is good.
How it's helping high boost when it's under the diaphragm and pushes up on the spring that holds down the valve.



Plus IIRC, there's no seal between the piston of the valve and the output, which would cause a minor boost leak.

Plus i'm reading this.
That damn second nipple on my type S MADE my boost leak. I guess it would open the valve under certain boost, around 14psi. I only have the one spring in, but dunno tired of screwing with it.
 
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O 16581 72452 5 said:
How it's helping high boost when it's under the diaphragm and pushes up on the spring that holds down the valve.
exactly when you have high boost it easier to have back pressure so with the smaller hose connect response is quicker. that way you can get the high pressure out faster. lmao
 

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whatthehell1051 said:
exactly when you have high boost it easier to have back pressure so with the smaller hose connect response is quicker. that way you can get the high pressure out faster. lmao
Yeah, but the valve is going to leak at high pressure that way, like the excerpt i pasted.
 
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O 16581 72452 5 said:
Yeah, but the valve is going to leak at high pressure that way, like the excerpt i pasted.
no because its the same pressure both ways. do a search on honda-tech. bunch of people there have them and have experience
 

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whatthehell1051 said:
no because its the same pressure both ways. do a search on honda-tech. bunch of people there have them and have experience
Yeah, it is the same pressure both ways, meaning about the only thing holding down the valve will be the spring because it'll no longer be putting positive pressure down. I'm not arguing it, i'm just stating my observation, it could be wrong, i'm just going by what i read and what made the most sense to me, i've read it's for low boost to help open it quickly/more efficiently because it's boost pressure that does open the valve, it's just vacuum assisted, if there isn't much pressure, it's harder for it to open to escape.
 
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O 16581 72452 5 said:
Yeah, it is the same pressure both ways, meaning about the only thing holding down the valve will be the spring because it'll no longer be putting positive pressure down. I'm not arguing it, i'm just stating my observation, it could be wrong, i'm just going by what i read and what made the most sense to me, i've read it's for low boost to help open it quickly/more efficiently because it's boost pressure that does open the valve, it's just vacuum assisted, if there isn't much pressure, it's harder for it to open to escape.
ok your say two different thing there but w/e
 
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