do all baileys dump valves hiss on part throttle?

C

coilerr88

Fresh Recruit
As the title says.i noticed it when I was on the motorway and on part throttle u can hear the dump valve open and it hisses is this because baileys are not great and the spring isnt strong enough and will this mean loss of power? As it will be like a boost leak
 
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Rory

Rory

Lifer
Baileys are fine if looked after.
One outside the house no hissing after 2 years in the car..
 
M

Murray

Member +
Rory said:
Baileys are fine if looked after.
One outside the house no hissing after 2 years in the car..
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4 years. TBH i think thats what they are meant to do. If everyones does it?
The valve needs pressure to keep closed so if there is no pressure the valve will just keep slightly open on its own spring/vacuum

Murray
 
MARK@CMBAUTOS

MARK@CMBAUTOS

Trader
Murray said:
4 years. TBH i think thats what they are meant to do. If everyones does it?
The valve needs pressure to keep closed so if there is no pressure the valve will just keep slightly open on its own spring/vacuum

Murray
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It's cause there single piston style that's why u get blow by
 
M

Murray

Member +
pilgrim_fgau said:
Its still reducing intake pressure below what it should be, and no other decent BOV does it
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Is it though? Just because you can hear a whooshing? Maybe the other ones do it to but are designed not to whoosh? who knows.
I might datalog my car with different BOVs and see whats what.

Murray
 
pilgrim_fgau

pilgrim_fgau

Member +
Well if u have a leak in the intake at any point, there will be less intake pressure than if there was no leak. It would be like having a loose intercooler pipe, whilst the bov is leaking anyway.

I also had a fake forge bov on my first glanza and it done the same thing, at about -5psi vacuum pressure, definitely killed thr responsiveness until the hissing went away
 
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M

Murray

Member +
pilgrim_fgau said:
Well if u have a leak in the intake at any point, there will be less intake pressure than if there was no leak. It would be like having a loose intercooler pipe, whilst the bov is leaking anyway.

I also had a fake forge bov on my first glanza and it done the same thing, at about -5psi vacuum pressure, definitely killed thr responsiveness until the hissing went away
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I get what you are saying and at the end of the day a leak is a leak, but IMO when the baileys is hissing on part throttle its not leaking. It is getting rid of excess pressure that aint required, Remember its controlled by the vacuum in the inlet manifold, when it sees boost it closes, when the boost drops off like on part throttle stuff and back into vacuum it will start to let off the pressure. I just think its more audible on the baileys due to the single piston design. Its a really simple valve at the end of the day.
Like above, if i get the chance to test another BOV i will, and try and record the datalogs:)

Murray
 
MARK@CMBAUTOS

MARK@CMBAUTOS

Trader
They do work it just cuntin annoying when u hear it blow by
My tial one and hks dont blow atall on part throttle neither do the blitz or greddy but all these have a diograms and are a totally different design
The bailey is a very old design and IMO were made for rs turbos and r5's but they do work !
They do do a better version its the one with the trumpet ! They don't blow by
But it would def be interesting to see ur data log
 
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