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The correct blow off valve

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You already have this so you just run a hose to the forge and there you go?
 
Roy 940 said:
It works perfectly well! It's closed @ idle and really no issue with it!

My setup :

http://[URL=http://s846.photobucket.com/user/Roy940/media/P1000118.jpg.html]
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What is loud? I can clearly hear it, it makes a nice FSCHIIIII sound!
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So use the pipe I have and run it post ic and pre intake. Is this actually considered a blow off valve?
 
Depends, that black hose with the nipple originally went above the turbo pre intercooler. (It is red in this pic and has no nipple.)

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This one has the exact hose but it is harder to see.

780-turbo-engine-bay.jpg
 
3rd pipe down on the left, that's the one that connects to the outlet of the turbo. I guess this is because it's off a 940 with the middle fed intercooler, which i can't even fit yet.
 
Roy 940 said:
Yes, it's a BOV vented to atmosphere...

About placement, nobody can say exactly if it's better pre-IC or post-IC... IMHO I prefer to have it post-IC, close to the TB.
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So should I just order that one?:roll: $150 lol as long as it makes choo choo noises well be alright.
 
Roy 940 said:
Yes, it's a BOV vented to atmosphere...

About placement, nobody can say exactly if it's better pre-IC or post-IC... IMHO I prefer to have it post-IC, close to the TB.
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While it all vents no matter where it's located, the purpose of it is to prevent back pressure on the turbo, I prefer mine as close to the turbo as possible, look at the factory CBV, it's mounted right on the turbo. Being close to the throttle body doesn't do anything for the TB, it's closed when the BOV is active so the TB doesn't care. It seems like the BOV's that require spring adjustment are kind of finicky, I put my SSQV on and it worked out of the box, I've never had to adjust it and never had any problems with it. It works on pressure differential not springs and you can hear it breathing every time I let off the gas when there's any kind of boost built up.
 
VB242 said:
While it all vents no matter where it's located, the purpose of it is to prevent back pressure on the turbo, I prefer mine as close to the turbo as possible, look at the factory CBV, it's mounted right on the turbo. Being close to the throttle body doesn't do anything for the TB, it's closed when the BOV is active so the TB doesn't care. It seems like the BOV's that require spring adjustment are kind of finicky, I put my SSQV on and it worked out of the box, I've never had to adjust it and never had any problems with it. It works on pressure differential not springs and you can hear it breathing every time I let off the gas when there's any kind of boost built up.
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I've read somewhere that the post IC (closest to TB) is better in term of engine responsiveness...
 
VB242 said:
look at the factory CBV, it's mounted right on the turbo.
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There doesn't really seem to be a right or wrong way, but I would expect that integrated CBV's are more of a packaging thing than anything else. Plenty of other cars with separate and post IC bypass valves stock.
 
For what it's worth I'm running a TurboXS RFL on TLAO chipped lh2.4 computers and I deleted my IAC crap. Runs better than when I bought the car.
 
Stiggy Pop said:
There doesn't really seem to be a right or wrong way, but I would expect that integrated CBV's are more of a packaging thing than anything else. Plenty of other cars with separate and post IC bypass valves stock.
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And when Volvo used the T3 without the built in CBV they used a Pierburg valve on the turbo side of the intercooler plumbed back into the inakte right before the turbo inlet. The turbo still has to pressurize all that plumbing once it's dumped from either side. I think the closer to the turbo the better, otherwise there will be more back pressure on the turbo when venting from the throttle body side while the IC and plumbing vent. There is a better side and it's as close to the turbo as possible.
 
VB242 said:
...The turbo still has to pressurize all that plumbing once it's dumped from either side. I think the closer to the turbo the better, otherwise there will be more back pressure on the turbo when venting from the throttle body side while the IC and plumbing vent...
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Why would that be? My lame (grade 11) physics hypothesis goes like this: the turbo pressurizes the intake, yes, but it also flows from turbocharger->throttle body. If it opens right in front of the TB, wouldn't the air still be flowing that way when it closes and the boost returns, as opposed to it basically flowing backwards to exit just after the turbo? Wouldn't it create a turbulence of some kind? Even if my thought is anywhere near reality, it would probably end up being an intangible change, anyways.
 
It takes time to vent the whole IC and piping, and during that finite amount of time there will be more pressure at the turbo discharge with the BOV on the throttle body side as opposed to the turbo side. The air doesn't all escape at one time, mine is only maybe a 1" port and following your logic it would be better to have more pressure available at the throttle body ie: having it vent near the turbo.
 
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