Aftermarket Bypass Valve? BPV

That spinning thing that makes all of the cool noises. OE and Aftermarket.

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kimokalihi
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Aftermarket Bypass Valve? BPV

Post by kimokalihi »

Should I get an aftermarket bypass valve if I'm running 18lbs of boost? Will the stock SS BPV start leaking boost once it gets over stock boost of 13 lbs?

I saw a video on installing an aftermarket BPV and they showed how the stock BPV was leaking boost after upgrading the turbo and other parts and running more boost. The guy that was doing the install and talking about how the BPV works and why it's a good idea to upgrade it was one of the guys at GoFastBits in Australia. He mentioned that when your turbo is making that crazy noise when you shift that is caused pressure built up in the intercooler being shoved back into the turbo and fighting the momentum of the turbine. The reason I bring that up is because my car makes that noise pretty loud on 13lbs and less. Is that normal?
Last edited by kimokalihi on Fri Jul 23, 2010 8:36 pm, edited 1 time in total.
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Legacy777
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Re: Aftermarket Bypass Valve? BPV

Post by Legacy777 »

I don't think you can definitively answer that question. It will depend on whether the stock valve is in good working order. If it is, it'll hold 18 psi just fine. I've been running close to 19-20 psi on the stock valve, and to my knowledge it was not leaking.

However, if the valve is not in good order, it may leak at 13 psi.
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asotwavb
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Re: Aftermarket Bypass Valve? BPV

Post by asotwavb »

Depending on your setup, maybe pressure test the charge pipes and see if its leaks at 18PSI
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kimokalihi
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Re: Aftermarket Bypass Valve? BPV

Post by kimokalihi »

I was going to do that but more like 20psi to be safe. But I can't think of how I would do it properly. I cannot get access to the inlet of the turbo due to the manifold being in the way and the silicone hose on the turbo. There's no way I'm taking that thing off again.

Could I hook up a pressure testing device to the end of the silicone hose (it has a metal insert to keep it's shape) and pressure test from there? Or would that damage something like the BPV or anything else running vacuum off that silicone intake hose?
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kimokalihi
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Re: Aftermarket Bypass Valve? BPV

Post by kimokalihi »

Oh wait, maybe I could disconnect the turbo and pressure test the Y pipe. I see what you're saying. I would just need to buy a piece of PVC and put a cap on it. Drill a hole in the cap and insert a pneumatic hose hookup. What do I use to gauge it? I don't have a compressor that you can adjust the PSI on. Maybe a hand pump would be better with an inline gauge?
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91 SS EJ20G Engine/Tranny/Diff Swap Build Thread Here
"Your testes are close to your bottom but you still play with them all the time." Jeremy Clarkson
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