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Nissan Turbo Stock Blow Off Valve

yogi000

By yogi000,
in Engines & Forced Induction

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yogi000 Mentor

yogi000

Posted
Posted

Hey ,

Yesterday i did the dodgy BOV modification by using a self taping screw to block the holes on the bottom of the BOV. Now by doing this the "blow off" noise i really loud......but what i wanna know is, is this noise coming from the blow off or is it the air going back thru the turbo pipes to the compressor???

Is this no good for the turbo???

i've done a search but just can find an answer.

P.S The car feels like it comes onto boost alittle stronger.

Thanks

George

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mad082 Grand Master

mad082

Posted
Posted

it is doing it louder because the air is suddenly depressurising suddenly, whereas before it was constantly leaking. have you still got the plumback pipe connected? if not then that is the problem. but when i did mine i noticed that induction noise was a bit less, and i thought the bov was louder, but it wasn't. it was just because the induction noise was less that it was more noticable.

Cubes Grand Master

Cubes

Posted
Posted
Hey ,

Yesterday i did the dodgy BOV modification by using a self taping screw to block the holes on the bottom of the BOV. Now by doing this the "blow off" noise i really loud......but what i wanna know is, is this noise coming from the blow off or is it the air going back thru the turbo pipes to the compressor???

Is this no good for the turbo???

i've done a search but just can find an answer.

P.S The car feels like it comes onto boost alittle stronger.

Thanks

George

Thats interesting... I found the BOV/Turbo was much much quieter coming on and once on boost with the psshhtt noise being the same volume but just slightly different. So yer what your probably experiecing is a quieter spool then when it does go psshhtt you hear it, where as before there was always a bit of noise so maybe the pshht was as much of a difference in volume.

I put mine back to standard as it affected drivability through the hills.

TTT Grand Master

TTT

Posted
Posted

what is the new sound that it makes?

Just like the stock sound but louder?

If so, that is fine.

If the noise is more like a fluttering sound, then it’s not venting..

As hard as it is to describe the sound via a keyboard I’ll give it a go..

Does it go..

Wwsshhhhhh

Or does it go.

Prrrrrrrrrrrrrrrrr

LOL..

If it’s the first, that’s fine.

Anyway, I’ll add one more little thing..

That stock bov bod, when done on an RB fitted with a FMIC seems to cause flutter instead of venting properly.

With stock side mount it works as it should.

Boost does come on quicker as it is not circulating ANY of the air so the transition between off boost and on boost is more instant. Hence that quicker spool feeling.

So what does it do?

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