Anyone heard this blow off valve before??

[351wcoupe]

I'm assuming its a stock bosch unit from a volvo.
Blow off.

I'm looking for cheap, stock off of something and effective. Is this one loud or quiet???

 

[351wcoupe]

I guess this is what it would look like installed.

 

[Stinger]

It's quiet because you have to plumb it back in bypass valve style or it will create a 1" vacuum leak.

Just watch ebay for cheap used bov's...I payed 45 bux for my RFL

 

[351wcoupe]

What do I search for to find the one you have?
whats RFL?

 

[1fastfox]

RFL stands for really F*&#!@# Loud.

its made by turbo XS. really nice my friend has one on his WRX and u can hear that thing coming a mile away. get one of those. its worth it.

 

[Stinger]

yeah, search for turbo xs, rfl bov, etc.

 

[351wcoupe]

ok I found them
I havn't decided if I want one really loud or not.
The only problem problem at this point is the price of those.

Does a bov cause it to run rich when it vents?

 

[JadeFalcon]

venting to atmosphere causes metered air to get expelled, meaning yes the motor runs rich for a moment, however from what I've gathered and seen, its not really a big issue as long as you get the right kind of bov.

 

[Stinger]

I've been unable to see a rich condition when mine vents and I have my wideband 02 plugged in...it's really a non-issue. You just have to get a dual piston (bailey, forge) or a unit with and adjustable spring pressure and tighten it down so it doesn't stay open at idle.

The RFL's go for ~70-80 bux used on ebay and sometimes you can find a good deal like me (45 bux).

Stinger

 

[351wcoupe]

what is the main purpose or advantage??
Is it to prevent lost boost between shifts? Because I never drop below 12psi from 18psi when I go down the track. Even then it slams back to 18 instantly.

Is it to prevent turbulence against the compressor blase and add to longevity? Because these turbos last well over 150k miles anyway?

Is there any performance to be gained?

 

[Stinger]

It is for both of those reasons...mainly to protect the turbo when you get over 15psi though.

 

[351wcoupe]

is there any performance gain other than maintained boost?

 

[JadeFalcon]

longer turbo life, and maintaining boost is your performance gain .

 

[351wcoupe]

longer turbo life, and maintaining boost is your performance gain .

yeah I can agree with that. but I was looking at less than a .1 of a second. The guage just flitters a tiny bit.