pic. of BOV... is this right?

[DavidT]

the vacuum line is ran to the bottom grey part. Is it right?

 

[Chris Benvie]

umm yea thats the BOV


if you're asking if its positioned right, i am not sure, its custom.


Are you expecting to hear a loud WHOOSH of air, its not a turbo.

 

[flosho]

Chris, I think he wants to know if he has the vacuum line plugged into the right spot?? David, do you have another pic, I cant see any vacuum line.

 

[DavidT]

yeah, I can get another one.
What is that on the SIDE... it doesn't have a fitting for a hose... but I have been advised to make SURE the vac. line is ran to the TOP part....so as usual...I am confused.
<----------- me and the s/c sho

 

[Chris Benvie]

AHH i see i see, well in that case I havn't a damn clue

 

[Lupo]

I do not know about that purple BOV, but with the more common HK BOV that you will see with most SHO Shop kits, there are 2 ports. The one on top is for a vacuum, and acts as a bypass with any vacuum from the intake. The lower one acts like a "pop-off valve", basically a safety feature that bypasses boost when a preset amount of pressure is reached. You simply use another hose from the intake, or tee off of the one hooked to the top. The screw on top allows you to adjust at what pressure this safety feature will activate. Most if not all of the SHO Shop setups do not use the lower port at all, but just simply leave it unhooked.

 

[Chris Benvie]

I think that BOV is custom as its a Greddy part.

 

[DavidT]

should you be able to hear the BOV?
Only sound I hear at times (besides a whistle) sounds kinda like a rattlesnake... odd description (I know)

 

[Lupo]

should you be able to hear the BOV?
Only sound I hear at times (besides a whistle) sounds kinda like a rattlesnake... odd description (I know)

Different BOVs and bypass valves sound differently. You can test if it's working by simply feeling the air discharge at the BOV when the car is at an idle. Then unplug the vacuum line from it, and see if it stops releasing air.

 

[Chris Benvie]

should you be able to hear the BOV?
Only sound I hear at times (besides a whistle) sounds kinda like a rattlesnake... odd description (I know)

I have heard that cars BOV and yes it sounds like a rattle snake. I told you it works, I have heard it. It just not going to sound like a turbo car.

 

[DavidT]

really Chris?
I was wondering though... I hear it sometimes WHEN I am ACCELERATING...

 

[Mike Kopstain]

Dave,

I'm not entirely versed with Marc's setup, but that valve might be set to relieve extra pressure to atmosphere at a set psi.

 

[Chris Benvie]

really Chris?
I was wondering though... I hear it sometimes WHEN I am ACCELERATING...

Uhhhhh i heard it when i let off the gas, when its accelerating, now that is just f'ed up.

 

[PanamaPat]

really Chris?
I was wondering though... I hear it sometimes WHEN I am ACCELERATING...

I would not expect for you to hear it when accelerating as the valve should be fully closed at that point.

Normally, they are set to open under vacuum, and close under boost. Mine is set to open at around 10-12 psi of vacuum.

Originally, the SS plumbed in only one of the two vacuum ports on the valve; the one that opens the valve under vacuum. This is the port that is on the same side as the spring adjuster bolt. The vacuum line was run from the top of the BOV valve port to a T-fitting in the vacuum line going to the pressure regulator.

The other port (under side of the valve) was open to the ambient. I've since plumbed this underside port, at Gary's suggestion, to the pre-throttle body side of the blower (installed a vacuum hose fitting off the discharge of the blower). The valve used to make lots of fluttering noises during decelleration, but now is much quieter and seems to either transition open or closed very firmly.

 

[DavidT]

so SHOULD you be feeling ANY air discharge at idle... because I do NOT...?

 

[Lupo]

so SHOULD you be feeling ANY air discharge at idle... because I do NOT...?

Yes, at idle, it should be in full bypass mode. Unless it's not working, or it's hooked up wrong, it bypasses a lot of air at idle. Very noticable.

 

[DavidT]

so what is the lower fitting (on the bov) for?

Why would there be 2 fittings anyways?

SO if it IS connected to the wrong fitting, what is it doing and what would I be seeing/hearing/feeling?

 

[Lupo]

so what is the lower fitting (on the bov) for?

Why would there be 2 fittings anyways?

SO if it IS connected to the wrong fitting, what is it doing and what would I be seeing/hearing/feeling?

As I stated in a reply above, usually the upper fitting is for vacuum bypass, and the lower one is a safety blowoff activated at a preset amount of boost. If you have you vacuum hose hooked to the wrong fitting, then your bypass valve will do nothing untill you reach a preset amount of boost (set by that screw on top), then it would release pressure.

 

[DavidT]

ooops! You DID answer that a LONG time ago.

I hope this isn't a repeat too:
is it ESSENTIAL that the BYPASS valve is hooked up properly? (as mine apparently is NOT)

 

[Lupo]

ooops! You DID answer that a LONG time ago.

I hope this isn't a repeat too:
is it ESSENTIAL that the BYPASS valve is hooked up properly? (as mine apparently is NOT)

Well if it's not hooked up right (or setup right, whatever) then it's not going to act as a bypass valve.