BPV question, compressor surge?

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robertpaige
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BPV question, compressor surge?

Post by robertpaige »

So I got the car and this was goin' on. The red circled areas have been capped off, and the green is the only line coming off of it. He said he capped them because it makes it better.. I dunno. After boost it's a fluttering sound which I believe is compressor surge? and i'm wondering if i'll get better performance if I route the return line back into the intake and i'm wondering if I left it like this that this could harm anything?

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James614
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Re: BPV question, compressor surge?

Post by James614 »

The only way it could make it better is if the BPV was leaking boost. But even then those BPVs are a dime a dozen, capping it off is a terrible solution. You won't blow up from it, but its extra wear on the turbo.
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Re: BPV question, compressor surge?

Post by Legacy777 »

Yeah, I would putting the bypass line back on as it's not good for turbo, and depending on the circumstances could cause turbo failure.
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robertpaige
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Re: BPV question, compressor surge?

Post by robertpaige »

Until I can find a hose, can I just unplug the BPV side and leave the elbow plugged or will that just give me an awful leak.. haha I am wondering if that will act like a BOV. Or maybe I can just borrow my friends BOV. I am definitely not trying to blow my turbo.
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kimokalihi
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Re: BPV question, compressor surge?

Post by kimokalihi »

It should function the same as a bov. But fix that right away. Its dumb.
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Re: BPV question, compressor surge?

Post by randomiam »

the capped areas look like they are what need to be connected in order for the bypass valve to recirculate back into the intake (like the factory setup)

in theory, with the BPV outlet blocked like that the pressure has nowhere to go but backwards into the system which is bad news for the turbo..

head to lowes and go to town on the plumbing isle and get that bitch recirculating again proper
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Re: BPV question, compressor surge?

Post by James614 »

kimokalihi wrote:It should function the same as a bov. But fix that right away. Its dumb.
Aren't Subaru BPVs open at idle?
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Re: BPV question, compressor surge?

Post by robertpaige »

I uncorked the BPV. It idles just fine, and it blows off. The car runs great still, doesn't seem to have any idle issues or anything I noticed. I gave it a spirited run. The sound is cool... :D
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kimokalihi
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Re: BPV question, compressor surge?

Post by kimokalihi »

It'll be ok like that as long as its not open at idle which I don't think it would be. But you should still fix it. It'll run lean for a second during shifts.
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robertpaige
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Re: BPV question, compressor surge?

Post by robertpaige »

Would it be harmful to have it like this for a couple weeks?
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kimokalihi
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Re: BPV question, compressor surge?

Post by kimokalihi »

Nah. You could probably run it that way forever if you like the noise but I've never done it so to be safe just replumb it like stock whenever you get a chance.
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robertpaige
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Re: BPV question, compressor surge?

Post by robertpaige »

Cool. As soon as it's payday i'll go get the hose.. i'm not really sure the best place to get that hose. I've seen people have Samco hoses that have the big opening for the BPV that shrink down to whatever the elbow is, like 3/4. Maybe I can custome fab some hose together.

edit: Patrick I didn't really think about that haha, i'll stop by home depot or lowes and get it back to the way it should be.
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Alphius
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Re: BPV question, compressor surge?

Post by Alphius »

Kimo, to be more accurate it will run rich during shifts with a vent-style BOV because it is ventine metered air. Less air, same amount of fuel=rich!
kimokalihi
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Re: BPV question, compressor surge?

Post by kimokalihi »

Isn't that what I said? His bpv is open to the air, no hose to recirculate the air.
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Alphius
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Re: BPV question, compressor surge?

Post by Alphius »

You said it'll run lean during shifts. It'll actually run rich. Just trying to keep correct info in here. :)
kimokalihi
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Re: BPV question, compressor surge?

Post by kimokalihi »

Ooooohhh. Oops haha my badness. I stand corrected. I meant rich I don't know what I was thinking.
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Re: BPV question, compressor surge?

Post by alexandermf »

Before I had my bpv rerouted back to intake mine was like yours where the elbow was just free to the air and as cool as it sounded my car was idleing choppy and sometimes dying as my maf was trying to compensate and ecu trying to learn it but as started before reroute it and you'll run smoother and not as rich
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