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Bov Positioning

flamo_damo
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flamo_damo Enthusiast

flamo_damo

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Posted (edited)

Hey guys,

Just thinking about this last night and I was wondering what the differences in running your blow off valve on the intake side ( coming from throttle body) or on turbo side (coming from turbo)

Now I have done a search and can't find a definitive answer so I thought I would ask, now if by running it on a different side whats better ie: running a atmo on intake side or say running a plumb back on turbo side? What would be better performance wise? atm I have no blow off vavle, but I'm looking a getting a blitz atmo blow off valve and I'm wondering where the best place to put it would be?

Any help would be much appreciated,

Damon

Edited by flamo_damo
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Sydneykid Grand Master

Sydneykid

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Hey guys,

Just thinking about this last night and I was wondering what the differences in running your blow off valve on the intake side ( coming from throttle body) or on turbo side (coming from turbo)

Now I have done a search and can't find a definitive answer so I thought I would ask, now if by running it on a different side whats better ie: running a atmo on intake side or say running a plumb back on turbo side? What would be better performance wise? atm I have no blow off vavle, but I'm looking a getting a blitz atmo blow off valve and I'm wondering where the best place to put it would be?

Any help would be much appreciated,

Damon

Simple answer, for the best response, is the closest to the throttle body that you can get. That way the ariflow doesn't have to reverse direction to vent, then reverse direction again when boost is required.

Cheers

Gary

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flamo_damo Enthusiast

flamo_damo

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:bunny:

Probably the only place I didn't look.

Simple answer, for the best response, is the closest to the throttle body that you can get. That way the ariflow doesn't have to reverse direction to vent, then reverse direction again when boost is required.

Cheers

Gary

Thats what I thought, so the standard position is best! Cheers champ

I sort of no what you mean ... maybe..

If you mean using a blow off valve in your exhaust, i,e on the turbo side then buy a wastegate..

A bov is designed to recirculated unused compressed air (obviously made by the compressor) back into your intake to keep the turbo spinning during gear changes and help reduce the technical term we refer to as dose, which is air forced back against the turbo (i.e possable damaging)

the intake does not use exhaust air (air comes through the pod filter btw) if you did youd run into abit of strife..

Am I on the same page as you or am i talking about different things?

if your talking about moving the bov, you can move it anywhere you want. just has to infront of the plenum...

Haha I think your on a different page to me haha, I probably didn't explain it the best but I got the answer I needed from SydneyKid

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paulr33 Grand Master

paulr33

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think about what you are asking ?

there is no way a bov in front of the turbo (ie; intake side) would work, as there is no pressure there once the throttle body is closed

the bov needs to be where the pressure gets trapped, ie; past the compressor wheel, but before the throttle body

an atmo bov is annoying and not-needed and will probably slow down turbocharger response on gear change

the std unit is a recirculating unit and it works fine for all applications

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flamo_damo Enthusiast

flamo_damo

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think about what you are asking ?

there is no way a bov in front of the turbo (ie; intake side) would work, as there is no pressure there once the throttle body is closed

the bov needs to be where the pressure gets trapped, ie; past the compressor wheel, but before the throttle body

an atmo bov is annoying and not-needed and will probably slow down turbocharger response on gear change

the std unit is a recirculating unit and it works fine for all applications

See that's what I thought, one of my mates had his pretty much running off the elbow on the turbo and I thought why the f**k would it be their? But thank you for the clarification!!!

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flamo_damo Enthusiast

flamo_damo

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Im pretty sure he was asking which side of the intercooler. There are arguements for either, and factory setups have it on either, so i dont think there is a major benefit either way

Thats what I was asking, but it seems having it as close to the TB the better!

Edited by flamo_damo
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R33Turbo Proficient

R33Turbo

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Posted (edited)
Simple answer, for the best response, is the closest to the throttle body that you can get. That way the ariflow doesn't have to reverse direction to vent, then reverse direction again when boost is required.

Cheers

Gary

i remember you were talking about this in some other thread about the best bov positioning. at the moment i put in HKS SSQV (the one with bolt at the back), and im having shittier response.

its got the rb25 adaptor so i just screwed it onto where the factory BOV goes onto, blocking the pumb back pipe. This is positioned so that the screw at the back of the BOV faces outwards (facing the ABS unit direction). is this alright or could this be a bad setup? Should it face the other way? cuz it didn't really fit facing the other way (all my previous BOV faced the other way and had no response issues).

Edited by R33Turbo
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PSI Parts Veteran

PSI Parts

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Posted
an atmo bov is annoying and not-needed and will probably slow down turbocharger response on gear change

the std unit is a recirculating unit and it works fine for all applications

Why would an atmo BOV slow down turbocharger response?

It should do the opposite because it's job is made easier by not having air running in the opposite direction than it's trying to push.

Recirculating is only really needed for legalities, I wouldn't use it for any other purpose. Hence the attachments that are available if you only want to run atmo on track days and keep it street legal the rest of the time.

post-28667-1211977223_thumb.jpg

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