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Hey this engine isn't mine just one I found on the net to illustrate my question. On my car the hose i've circled below has been removed and the ends where it joined on have just been sealed off with big rubber cap things. Just wondering why this would've been done, and if I should remove the caps and rejoin the hose. I remember the engineer who looked at it when it was imported said i should fix it cuz it could end up blowing my engine up or something.

rb20det.jpg

Edited by Lithius

So what they've done is block off the stock BOV? Where does the air go instead? Any idea why they would've done this?

I'm just wondering if I can take the caps off and put a little bit of hose in there to rejoin it all. Or whether I should even just leave it how it is... If the BOV isn't hooked up how does it release pressure?

Edited by Lithius

I met a guy a while back who swore on his life and bet his balls that bovs decreased performance and hurt the engine, no matter how much i argued with him, he couldn't understand.

Sorry, just thought i'd mention that.

Bov's definitely do not hurt the engine.

Having no bov doesn't hurt the engine either.

There is the issue of having no bov causing compressor stall when you jump off the throttle, causing it to have to spin up again.

When making shiet loads of power some have noticed a decrease in lag between wot gear changes by running a larger bov.

Who knows.. Who cares.. :)

The theory is that the BOV allows to compressor to keep pumping during gear changes and times of closed throttle.

On full boost and WOT, the air from the turbo compressor is flowing into the engine. During a gear change, the throttle snaps shut, blocking off the path for the air into the engine. However, the compressor keeps pumping. Eventually it will reach the limit of its capacity to pump air and start to slow down. So when the throttle opens again, the compressor needs to spool up again.

Now, if you release the pressure, via a BOV, the compressor can continue to work at optimal performance. So when the throttle opens again, the compressor is still at it's optimal speed and pumping capacity, gaining immediate response from the engine.

I'm sure if BOV's detracted from perfomance, the manufacture's would not have invested millions of $$$ developing the engine with a BOV attached.

Thanks for all the input guys.. I joined it back up with some radiator hose type stuff, does seem to be a bit nicer between gears when i'm giving it a bit. So there's nothing else they would've changed to complement that? Like the electronic boost controller and stuff will still be fine?

yea you should be right, by the looks of it the person before you simlpy turned the BOV into an atmo one. This does not effect your turbo but it would make you car run rich and possibly stall due to incorrect air flow meter readings.

Anyway, this is an easy fix and there should not be any other BOV related things for you to worrie about.

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