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Discussion Starter · #1 ·
I have a few laying around and I am thinking of opening one of them and testing the rate of the spring inside. I'm wondering if changing it for an upgraded spring would help it to stop leaking in the 12 psi and up range? of course it would still only be useful in the 12-16 psi range anyways, but justa thought.
 

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Only that apart from maybe needing to hold more boost (not for me, I'm only running 11psi) I don't see the point in doing anything to the stock unit. Boy racers need to hear a "psssst" to remind themselves they have a turbo, but of all the things I'd like to do, altering the BPV isn't one of them.

Actually that not quite true, I'd like to move it so it was engine side of the intercooler so the recirculated boost was being cooled. I think if 6" back from the TB is the best position for a BOV, it would be EVEN MORE benificial to have a BPV positioned there. The VAF to Turbo & Cooler to TB pipes run so close to each other at that point, it would be a simple conversion.
 

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I occasionally hear it through my K&N under certain conditions. There's a double apex right turn on the way home from work that I hold 2nd at 3/4 throttle till I'm onto the 2nd apex - WOT - 3rd. As I lift for 3rd the BPV sound resonates off a stone wall on my left.
Achieving the sound is not really something that I would set out to get(ie. spend $0.01 to get) but if it happens, it happens.

Do you have an opinion on the BPV location?
 

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Discussion Starter · #6 ·
I'm of the same opinion as you that the BPV or BOV should be placed AFTER the intercooler, although for BOV it really shouldnt matter much. I think that with a BOV placing it AFTER the intercooler is more of a negative, if you have it close to the throttle body and it blows off, it blows off alot of that pressure that should be going into the intake manifold, causing richness and undesired backfiring.
 

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I don't think the position of a bov matters as far as backfiring is concerned, if anything, you'd lose more charge if the bov was before the IC because of the psi drop across the IC would mean greater mass of air to escape.
I beleive the idea of "close as possible to the TB" is because that is where the compressor surge starts, therefor reducing the effect of surge more efficiently.

*edit* That was hard to read, I'll clarify. The pressure (psi) in the "intercooler to throttle body" pipe will be less than in the "turbo to intercooler" pipe. This is due to pressure drop from a restrictive intercooler. Therefor, a 1 second vent would lose a greater volume of air from the higher pressure pipe.
 

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For 2 reasons.
1) To cool the recirculated air
2) Eliminating compressor surge at the source (TB) & keeping the associated turbulance away from the turbo. The same reason it is the place of choice for a BOV.

*edit* Maybe 3 reasons. A shorter vacuum line to actuate the BPV may (i have no idea) be benificial.
 
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