Question about boost and the stock BOV

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Hey guys, I have a quick question I was wondering about and maybe you guys can help answer it. When it comes to cars I am pretty mechanically inclined and can figure my way around the engine as I have replace transmissions, clutchs, sensors basically anything that goes wrong on a car I can pretty much figure out and fix myself well I have a 2018 civic SI and a turbo engine is still kind of new to me, so I have a PRL cold air intake a new exhaust and ktuner v2 w/ TSP stage 1+ Tune. Well when my psi hits 18+PSI I can hear the discharge/blow-off from the turbo going threw the stock BOV as when it does it I can clearly hear the sounds on the right side of my engine bay while driving. And no it’s not the sounds I’m hearing from the intake. I just want to make sure it’s normal to be able to hear that coming from the BOV. As I said it’ll do it while I’m on the throttle and boost hits 18+. Sorry if it’s a noob question I’m just new to turbo cars and am trying to wrap my head around this one lol ?
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The factory ECU uses the bypass valve as a form of boost control. As long as it's not literally venting all of your boost pressure at that point (while still under acceleration) it is likely behaving as it should.
 
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The factory ECU uses the bypass valve as a form of boost control. As long as it's not literally venting all of your boost pressure at that point (while still under acceleration) it is likely behaving as it should.
I believe it might be venting all my boost Bc I can hear it like it’s all going out the BOV as I get to the higher PSI bpost levels. That’s what I was mainly wondering was if that’s what it’s doing and it was venting the built up boost. I say that Bc even when pressing the throttle and the boost builds when it does that my boost drops before I even let off the pedal
 

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I believe it might be venting all my boost Bc I can hear it like it’s all going out the BOV as I get to the higher PSI bpost levels. That’s what I was mainly wondering was if that’s what it’s doing and it was venting the built up boost.
The stock system does not vent air to atmosphere, its a bypass valve that bleeds air back into the compressor inlet. If you are hearing escaping air you either have an aftermarket blow off valve or a boost leak.
 


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Did you come by your Si used?
I did, but it only had about 30k miles on it. I got it maybe 3 months ago or so. It did have one of those vent to air BOV plates that you put in between the turbo and the BOV and it vents the boost to air when you let off the throttle. But I took that off when I did the cold air intake Bc I read everywhere they were more harmful then anything. It was on the car when I got it though.
 

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The stock system does not vent air to atmosphere, its a bypass valve that bleeds air back into the compressor inlet. If you are hearing escaping air you either have an aftermarket blow off valve or a boost leak.
With an aftermarket intake installed it is certainly possible he is hearing the factory bypass valve, I have heard it before myself.
I believe it might be venting all my boost Bc I can hear it like it’s all going out the BOV as I get to the higher PSI bpost levels. That’s what I was mainly wondering was if that’s what it’s doing and it was venting the built up boost. I say that Bc even when pressing the throttle and the boost builds when it does that my boost drops before I even let off the pedal
If it's venting all boost, it should feel like all of your power goes away at once. It would be very noticeable. That being said, I don't know if there are any documented cases of a CivicX bypass valve failing in that manner.
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