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Hey guys,

A while ago there was post here, where someone installed a new FMIC on their skyline and it really slowed the BOV flutter down. I couldn't find that post, but does anyone have any ideas to what is going on and how I can rectify the problem???

Mine since the installation of the cooler has turned to a slow annoying chatter, when gears changed at lower RPM. However occassionally it will be fine. I have unassembled, cleaned and lubed it up before putting it back but still the same...

I am still running the same boost (9psi).... oh and it just comes on hardly any accelleration (boost gauge shows 5-10vac). My bov is a Turbosmart Vee Port

Turbosmart Vee Port (pic attached)

Any ideas???

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Guys,

The setup on the car is exactly the same as before. The only thing done was the installation of the new FMIC.

Other than that it is the same BOV as always running the same boost and same pod filter.

Although I had to tighten the bleed valve after installing the cooler, cos the boost kept creeping 4-5psi at high revs. (don't know whether thats normal either???)

But my concern is the slow chatter (like metal on metal sound) rather than the smooth flutter. Also at hight revs (redline even) there is no more clean pshh, but more of a flutter.

Any ideas???

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Is there a reason why you guys are NOT using stock bov?

If you have it still, just put it back on and go for a drive and see how much better the car behaves, drives and sounds.

Nah man I bought the car with the bov valve on it. I wish I had the standard one so I could try it. What are they worth??? How do they sound??? Also do you think the standard one would reduce the popping out the exhaust???

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1.) they cost like $20 second hand.. just post a wanted add in the wanted section.

2.)they just make a whooshing sound.

3.)yes it will reduce or eliminate the popping sound from the exhaust as the car won't run rich in between gearshifts as it will be plumback.

and it out flows much more than your stock turbo will ever be able to throw at it.

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Think about volume here guys.. you've increased the boosted volume by fitting a bigger cooler and the BOV can't get it all out in time before it bounces back to the compressor...

Try adjusting the BOV to it's max setting..

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Think about volume here guys.. you've increased the boosted volume by fitting a bigger cooler and the BOV can't get it all out in time before it bounces back to the compressor...

Try adjusting the BOV to it's max setting..

Is that max tightnening??? Cos I have done that and no change... Have not tried loosning it but that would be going backwards right???

1.) they cost like $20 second hand.. just post a wanted add in the wanted section.

2.)they just make a whooshing sound.

3.)yes it will reduce or eliminate the popping sound from the exhaust as the car won't run rich in between gearshifts as it will be plumback.

and it out flows much more than your stock turbo will ever be able to throw at it.

Also why do people go after market if the standard one is so good???

Will it fit in exactly the same spot as the current one (will post pics tonight)???

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The "chatter" is just the air blowing back through to turbo and being chopped up, like when you blow backwards through a fan. Loosen the blow off valve and it will fix it. Tightening it increases the spring tension therefore requires more to open it. Personally if your running an AFM and aftermarket BOV you are better to have some low-rpm chatter. I had mine set so that more or less anything under 1-2psi the bov wouldn't open. Every time the bov opens it pumps a load of fuel through...

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The "chatter" is just the air blowing back through to turbo and being chopped up, like when you blow backwards through a fan. Loosen the blow off valve and it will fix it. Tightening it increases the spring tension therefore requires more to open it. Personally if your running an AFM and aftermarket BOV you are better to have some low-rpm chatter. I had mine set so that more or less anything under 1-2psi the bov wouldn't open. Every time the bov opens it pumps a load of fuel through...

No I mean its a chatter (almost like metal on metal). It used to make a nice flutter @ low rpm and clean pshh @ high boost like yours.

But now its just annoying. I have tightned it all the way the its still a slow chatter.

Not only that I hardly need throttle for it to go off... Like changing from second to third @30km/h and under 2.5rpm (on the boost gauge the needle is between 5-10vac) and there it is again.

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Marcus.

listen.

you need to LOOSEN the bov (on top it says the direction to turn for SOFT.. go that way).

loosening it will make it ACTUALLY blow off and go pssshh..

the stock bov sits exactly where your one is, and plumbs back in to that black pipe to the side of it which is blocked off.

see pic of a stocker..

1105_10mg.jpg

the chatter sound you keep saying is the same sound as you had before but the pitch has changed now due to the new intercooler.

more room in the intake system now so sound changes.

so..

1.) loosen your bov

or

2.) get stock bov.

I say option 2 and sell the turbofart one to some Fast fours forum guy for a couple of hundred.

why do people get aftermarket? 99% of the time, it's because they like the sound or the look, or the sticker it comes with.

the other 1% of the time, they have a car that is making so much power that the stock setup can no longer FLOW enough air... but this doesn't happen till way high boost and air flow levels.

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