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Discussion Starter · #1 ·
what do you guys think would happen if i disconnected the huge tube that routes the blow off of the stock block off valve? do you think it would go pshhht! or not. my guess is not because aftermarket blow off valves have a valve that is designed to make noise. am i correct in this assumption?
 

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i would honestly leave it alone. you don't want to just remove it. it is the valve that releases the pressures from a spooled turbo. without it you will not have have the correct boost.


DR
 

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I think some people have tried it. In concept it should work but I don't think it does in application. Don't forget you'll need to cap off the return hose as well. The BOV has NOTHING to do with boost pressure unless of course it's leaking.
 
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Discussion Starter · #4 ·
when you put in an aftermarket blow off valve like a blitz or hks does it come with something to cap off the huge hose from the stock blow off valve? if not what product have you guys used to cap off that tube
 

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i ditto CH92115's question. i noticed on the blitz BOV from GOD's pics and video. the hose is connected to the BOV, is that the hose that sends the air to the intake manifold?
 

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also, what does that tube do that sends the air from the stock bov to the intake manifold other than make sound come out? is there a downside to getting an aftermarket bov that does not let air go back into the intake?
 

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what do you mean that it keeps it shut and tells it to open? intead of a vaccum hose, what does an NA motor have to tell the intake to be open and closed?
 

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mario,

Naturally aspirated cars don't have a BOV. They have a throttle plate. Time for a little BOV 101.

The Blow-off Valve (BOV) or "bypass valve" release the high pressure intake charge aft of the turbo and before the throttle plate or "butterfly." NA cars don't have a pressurized intake charge, so no such device is necessary. The BOV remains closed while the turbo feeds air to the engine passed the open butterfly, which is wired directly to your gas pedal. When you let off the gas pedal suddenly, you get a sudden increase in pressure at the butterfly which creates a shockwave that travels back to the turbo compressor. A BOV receives a vaccum signal from the small hose on the top when the throttle is closed and it pulls open a spring-loaded piston which releases this high pressure air to the atmosphere or a later point in the intake. This helps the turbo maintain boost and increases its lifespan.

-Jim
 

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OH!

Jim,

Thanks for the quick lesson. Being new to all this, I was a little unsure about it as well.

Rod
 

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haha thanks PlatinumWRX i know NA cars dont ahve BOVs. i guess i didnt word my question right. but you answered it. i was looking for what an NA car has equivalent to that vaccum hose

thanks man u smart!
 
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