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Plumbing Back Atmo Bov's

ZRBE

By ZRBE,
in Engines & Forced Induction

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SargeRX8
SargeRX8

You dont need to bash it. When on boost theres 12 or what ever boodt you're running coming through the silicone hose on your bov pushing down on it to help keep it shut. So as long you've got some spr

GTSBoy
GTSBoy

Yes it is that easy.....except that you have to be able to bolt it all together once it is welded up. So a little thought during the "design" phase can save you a lot of swearing later. Main point o

shaunus
shaunus

Just take the plastic piece out from the vent on the SSQV. Will be much quieter and not make that high pitched whistle. I also couldn't stand the SSQV sound. This worked. Try it.

C4a0s Proficient

C4a0s

Posted
Posted

you're kind of killing your own arguement there though, if "The effect of opening the BOV is felt everywhere in the inlet tract within a couple of milliseconds of it cracking open." then the assertion "The BOV should be physically located close to the throttle body" - a cpl of milliseconds, it wouldn't matter where you put it, and so you could mount it whereever was most convenient and any performance advantage would be negligible if we're talking a couple of milliseconds.

this is interesting... my thoughts...

After the throttle body is closed, the system (between throttle body and outlet of compressor) is a pressured closed system correct? in a pressured closed system of air, it shouldnt matter where the "hole" is located cos the idea is to relieve pressure. Just like how the BOV is on the pipe at a 90 deg angle. As long as u have a hole somewhere in the system, pressure will be lowered.

However, in addition, I think GTSBoy is also talking abt airflow and this disruption in momentum if the BOV is located far away from the point of direction reversal. :)

scotty nm35 Grand Master

scotty nm35

Posted
Posted

Damn... How bad is it?

What would you do differently?

The afm is going to detect the returning air as the bov return isn't facing the turbo compressor at all. It will more likely go back through the afm and cause reversion.

The hose is just wrong. I would have placed the bov and return so they faced each other, so there was only a short hose with little bending.

Why is the intake smaller than the turbo and afm? I would have done 3 inch or 80mm, not 2.5 inch.

ZRBE Experienced

ZRBE

Posted
  • Author
Posted

The afm is going to detect the returning air as the bov return isn't facing the turbo compressor at all. It will more likely go back through the afm and cause reversion.

The hose is just wrong. I would have placed the bov and return so they faced each other, so there was only a short hose with little bending.

Why is the intake smaller than the turbo and afm? I would have done 3 inch or 80mm, not 2.5 inch.

Too be honest I've done nothing to the car other than change BOV's.

Everything is left the way I purchased it..

I couldn't make the hose point upwards to get a smaller hose because when my bonnet is closed there is NO room at all..

Smaller intake in front of the turbo.. Too be honest I didn't really notice it was smaller.. :/

This is gay.... Haha

So where my BOV is plumbed back.. It should be facing towards the turbo, so it doesn't go back through AFM?

ZRBE Experienced

ZRBE

Posted
  • Author
Posted

Too be honest I've done nothing to the car other than change BOV's.

Everything is left the way I purchased it..

I couldn't make the hose point upwards to get a smaller hose because when my bonnet is closed there is NO room at all..

Smaller intake in front of the turbo.. Too be honest I didn't really notice it was smaller.. :/

This is gay.... Haha

So where my BOV is plumbed back.. It should be facing towards the turbo, so it doesn't go back through AFM?

Nothing the the engine**

ZRBE Experienced

ZRBE

Posted
  • Author
Posted

And as Scotty mentioned, the bov return should be angled so it points at the turbo.

Okay.. More welding & money.. :(

I'll grab a metal intake pipe as big as my compressor wheel? 3"

Weld on a fitting pointing towards the turbo and that BOV can only point up or down.. I can't turn it any other way, Bleh.. Lol

Thanks heaps for helping a noob import owner out :D

ZRBE Experienced

ZRBE

Posted
  • Author
Posted

Really? I have the same bov and it swivels around, just loosen the nut on the back of the 2 bolt adapter.

No nut on bottom of adaptor?

You don't mean the one on top?

Before I put it on I tried moving it and gave up because I thought it was fixed on.

Ben C34 Grand Master

Ben C34

Posted
Posted

this is interesting... my thoughts...

After the throttle body is closed, the system (between throttle body and outlet of compressor) is a pressured closed system correct? in a pressured closed system of air, it shouldnt matter where the "hole" is located cos the idea is to relieve pressure. Just like how the BOV is on the pipe at a 90 deg angle. As long as u have a hole somewhere in the system, pressure will be lowered.

However, in addition, I think GTSBoy is also talking abt airflow and this disruption in momentum if the BOV is located far away from the point of direction reversal. :)

I think what you are forgetting is that the air has mass, so having to turn around and go the other way isn't the best as going out a bov close to the throttle body.
scotty nm35 Grand Master

scotty nm35

Posted
Posted

No nut on bottom of adaptor?

You don't mean the one on top?

Before I put it on I tried moving it and gave up because I thought it was fixed on.

There is a two hole nut on the bottom, correct? (where the entry is) The top one is just the air fitting.

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C4a0s Proficient

C4a0s

Posted
Posted

I think what you are forgetting is that the air has mass, so having to turn around and go the other way isn't the best as going out a bov close to the throttle body.

actually no... didnt forget that thats why i mentioned abt momentum as well.. which is why i agree that it shd be closer to the throttle body. :)

Rolls Grand Master

Rolls

Posted
Posted

Damn... How bad is it?

What would you do differently?

Move the BOV about 10cm upwards so the hose only needs to be 1/10th that length, also use a hose that is the right shape (curved) so that it isn't full of nasty curves. The reality is no matter how backward your setup is it will still work fine, hell no bov works fine, but if you are going to spend money doing it, don't make it look agricultural spec like that, looks embarrassing to look at!

ZRBE Experienced

ZRBE

Posted
  • Author
Posted

Move the BOV about 10cm upwards so the hose only needs to be 1/10th that length, also use a hose that is the right shape (curved) so that it isn't full of nasty curves. The reality is no matter how backward your setup is it will still work fine, hell no bov works fine, but if you are going to spend money doing it, don't make it look agricultural spec like that, looks embarrassing to look at!

I know hahaha I have a new hose on now that isn't kinked.. But same problem just after it starts making boost (when the screamer is about to open up) it feel like the car shifts down a gear..

For example: The feeling when you go from 3rd to 2nd at about 70kms??

Rolls Grand Master

Rolls

Posted
Posted (edited)

So when the car makes boost it gets faster? That sounds pretty normal dude lol

Or do you mean when its already on boost it feels like the torque drops off at redline? if so that is normal, you get a big whack of midrange torque with the stock turbo around 4-6k then the torque drops off by redline as the tiny turbo can't provide any extra air. If you want that feeling to redline you need a bigger turbo.

Edited by Rolls

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