ok, so i searched and looked thru the FI section and couldnt find anything on this. Adjustable BOV's. why are they adjustable and what does it do when u turn the knob clockwise for harder and counter clockwise for softer. http://www.turbosystem.com/engine/Tu...martHRCBOV.htm

any one?

 

i thought the difference was that it would blow harder or softer....lol. blow me harder please..i dont know

 

haha crazy ass. like does it hold more boost before releasing the air? can u make it where it will only open with a certain amount of pressure?

 

Has to do with the amount if vaccum/boost you car is running, IIRC

 

ok, but does it make a different sound depending on how hard or soft u set it?

 

Usually if you have it set up tighter/harder, it will be a louder pop off when it releases, due to greater spring pressure, but there are many factors involved. Try one and see what happens.

 

so it will close quicker as well? if set harder? and when set softer let the air out in a sputter type form?

 

I really should know this stuff, But i dont remember most of it because 9 times out of 10 you dont/shouldnt have to mess with it

 

Yeah, it should close quicker too. Its basically like putting a stiffer spring in there, thats all. The sputter is usually surge, so again that depends on the turbo and setup on the car in question.

 

oh, ok. cuz i was looking at Hahns billet alum BOV im getting with my kit and was curious. thanks for the help guys

 

It allows you to adjust for the response. Every car has a different vacuum. So if you tighten the spring, it wont open until the BOV reads more vacuum. Some BOVs require you to put a different spring in for the amount of vacuum your car has.

 

ok i kno what vacuum is but how does it read it? i kno a Vacuum line gets ran to it on the top, but how does that work. i even googled it and tried learning how they workd and couldnt find any info

 

When the BOV sees vacuum from the line attached to the manifold, it opens letting the positive air pressure left in the charge piping out so the turbo can still spin forward.

 

ya, sputtering only occurs when the piping is plastic and flexes... major thing one the mazdaspeed protege almost sounded like a turkey, the plastic piping was only 2.5 inches but would flex to 3.0 during pressure when the pressure is released it pops back down to 2.5 but its plastic so it creates a shuttering effect. this is what caused it to sound like a turkey...

now sometimes on drift cars u will hear a similar sound but that is them getting on and off the throttle to control the turn and they are hitting and releasing the bov over and over which creates a similar sound...

the harder and softer generally from my experience is a sound, its what you perfer, harder will be quicker and shorter = louder, where as softer will be slower and longer = quieter... comes down to preference but if your going to be dragging the car or racing i'd say harder is better because if you get back on the throttle while the bov is still open your not going to be building boost until it closes.

 

i would think it just adds more or less pressure so it holds more or less boost

 

you can't adjust boost from a bov... that setting might affect how much boost it takes before it will release... but i doubt that even.

 

thx knoxbox. what u said in the previous post sounds reasonable understandable. and on drift cars i can see that. i know automotive and F/I engines. just i didnt kno about how BOV's worked clearly. i just wanted to fully understand them. i kno how they work like mechanically, just not how the harder softer thing works. but u answered it. thank you.

 

i could be wrong but like i said in my experience on my mazdaspeed with a greddy type s bov... it worked better for me with all the way hard, still had the flutter cause i had plastic pipping but with LOUDER, QUICKER, SHARPER sound... put it this way, i made a lady in a minivan with her window down run off the road when i hit the bov next to her, another time a lady was jogging on the side of the road with a mp3 player and she jumped off the sidewalk. i'd say you could have heard it from football field away easily. im sure the amount of boost as alot to do with how loud the bov is as well i was boosting about 14 psi in my mazda.

 

that sounds pretty sweet. and i love the snappy BOV sound if u wanna call it. how its a loud psshh in stead of a long quiet one. and i do drag the car. so... but ill try diff settings and prolly record and make a documentation of it for turbo guys here. to see how everyone likes the sound. i think it might be kool

 

ok so my friends are telling me that i can put a bov on my 05 cobalt ss bt i dont see how if anyone knows how or have seen it done let me know

 

no it wont work. PERIOD

 

The problem is that no one knows the main purpose of a BOV.

If your first factor for deciding what BOV to go with is, "What sounds better?", you are a ricer. The sole purpose of a BOV is eliminate compressor surge to save your turbo. I have, and will always support the Synapse BOV. It 100% completely eliminates compressor surge and is faster reacting then other BOV's because of the no diaphragm design. The Hahn looks like a nice piece but it needs to be dialed in actually for the vacuum spike otherwise it won't open when you let off. And if you gradually let off the throttle, they usually don't release.

 

say wut? really? i dont know much about bov's. wanna show me wut ur talkin about or explain better on this diaphragm design?

 

http://www.youtube.com/watch?v=MU5Y6...eature=channel

 

i see very nice vid