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Discussion Starter #1
I know your bov runs off vacum but how do you set the bov? My bov was orig. set to run w/ 7 psi. and now I am running 20. It also has been jacked with so the settings are all off, now I don't know what it is set at. Can you expain how to set these damn things. At 7psi. it use to pop off real loud, now I don't hear that, but rather the turbos just spooling down when I let off the gas, no pop or woosh! Also every time I shift the car pops real bad.
 

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I gots famous friends
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I don't know how to tell you to adjust an adjustable BOV, never heard of one really. Go check over on www.turbomustangs.com and ask in the Main Tech forum.

Stop driving the car wih it in that condition, you are shocking the hell out of the compressor wheel when you let off the throttle and that compression wave slams back into it.

Seriously you are asking for trouble without a properly functioning BOV.
 

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dont know how to adjust them but your not doing your turbo any good with 20 psi of air trying to spin your compressor backwards when you let off the gas
 

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Discussion Starter #4
Yeah I post on turbomustangs.com too. Shane Hill has been trying to help me out with my combo and I asked him the same question and he hasn't got back to me yet. I just posted up on here to see if anybody knew. I know you have to set it with a vacum pump cause that is what operates the bov. I believe you have to find where the boost dosen't blow the valve open but, the vacum does once the t/p closes. Though i could be wrong.
 

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Discussion Starter #6
It is an HKS bov that incon specified for their kits.
 

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KOTS
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Your bov physically has a spring in it? Hrm weird, mine was just ran off of intake vacuum on the top port and compressor pressure on the side port. Those two act on each other and pull the piston up or down to release the pressure.
 
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BOVs are not adjustable, really except for some that you can increase the tension a little, but it doesn't really effect the point at where they open. Are you sure you're not referring to the wastegate?
 

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KJ94GT said:
BOVs are not adjustable, really except for some that you can increase the tension a little, but it doesn't really effect the point at where they open. Are you sure you're not referring to the wastegate?
That's what I am wondering, too. I am trying to figure out why a BOV would need any kind of a spring. Most just have diaphram.

Mine just has one vacuum line going to it.
 

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KOTS
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I was thinking the same thing hehe.. Ive never seen a bov with a spring in it. Most just run off vacuum.
 
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Yep. My 50mm Tial is not adjustable at all. But an old HKS was adjustable for hard or soft blow off, but it still didn't effect when it opened.
He must mean wastegate.
 

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KOTS
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KJ94GT said:
Yep. My 50mm Tial is not adjustable at all. But an old HKS was adjustable for hard or soft blow off, but it still didn't effect when it opened.
He must mean wastegate.
Same with my turbonetics bov, its not adjustable at all... two vacuum ports and a piston thats about it heh.
 

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Discussion Starter #13
Mine has a screw at the top so you can adjust the tension of the piston from either hard or soft. The bov is what makes the loud whoosh sound when you let off the gas right? It use to be real loud at 7psi and now with my new combo I don't hear it at all. When a turbo car does a burn out, or shifts gears you hear the bov and the whoosh.....but not on mine thats why I think it is not working or not working properly. If your bov tension on the piston is real soft then the 20psi of boost could blow it open causing boost to bleed off right? And if it was too hard, then the vacum may not be able to open the piston?

I am new with trying to push the limits of this turbo kit. (Incon 800 tti)

Ok, you guys said wastegates. My boost is set at 20psi and when it goes higher then 20psi the actuators open and the excess bleeds out of the wastegates right? This limits boost so you can't get overboosting? I see a consistant 20psi limit nad no more. My problem is when I let off the throttle I actually hear the turbo spooling down sort of like a supercharger whine. I don't hear the bov sound. Also, when I shift the car at 6500 rpm and let off the gas it pops between shifts. If I powershift I don't really hear a pop.

I been to turbomustangs too asking the same questions but I'm just trying to get more opinions on why the car does this.
 

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93coupett said:

I am new with trying to push the limits of this turbo kit. (Incon 800 tti)

Also, when I shift the car at 6500 rpm and let off the gas it pops between shifts. If I powershift I don't really hear a pop.

You shouldn't be letting off the gas when you shift with a jericho. At least your friend said it was a jericho.
 

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Did you hook up the vacum line to a source that will see vacum when the throttle is closed? i.e. intake manifold, vacume tree
 
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You could have the BOV hooked up wrong, or it's stuck. Have you tried opening the BOV by hand? If you can't, then it's stuck because they're not difficult to open. They're not super easy, but not impossible either.
 

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Discussion Starter #17
All vacum lines are hooked up. There is only one that goes to the bov and it is hooked up to the tree on the intake. Also all vacum lines that are not used are plugged up.

I know I shouldn't be letting off the gas when I shit but sometimes I do. Once the car is running right and not banging out I will not let off...but sun. since it was I was trying to be a little conservative. We also had the rev limiter set pretty high thinking that was our banging problems but it was timing. Once we get it tuned and it runs right, I will powershift.
 

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Discussion Starter #18
We have had the blow off valve off and it is not stuck. I can push it in with my fingers but it isn't easy. I have to take both of my thumbs and force it up in there. There is only one way it goes on and there is one vacum port. If I decrease the tension, it gets easier. When I rev the car up in neutral to about 4000 I see about 19psi of vacum. At that time, I can stick my hand underneath the bov and feel quite a bit of air coming out of it. Is this normal? Should any air get through the bov under non boost cond.? Of course when you get under boost you have no vacum to open the bov and it will only open when the t/p is closed. Hell, it could be working and just dose not pop off real loud...who knows? Although it did before.
 

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93coupett said:
I know I shouldn't be letting off the gas when I shit but sometimes I do.
You are right about that! You could be there all day.

Larger turbos with 20 pounds of boost are going to take longer to spool down than smaller turbos with only 7psi. If the car runs fine and you still make plenty of boost immediately following a shift then whats the problem? The BOV stops the turbos from trying to either spin backwards or completely stop when the throttle is shut, this way they can get right back to making boost again when the gas is back on. The only thing I'd worry about would be the valve leaking at anything over 7psi.
 

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93coupett said:
We have had the blow off valve off and it is not stuck. I can push it in with my fingers but it isn't easy. I have to take both of my thumbs and force it up in there. There is only one way it goes on and there is one vacum port. If I decrease the tension, it gets easier. When I rev the car up in neutral to about 4000 I see about 19psi of vacum. At that time, I can stick my hand underneath the bov and feel quite a bit of air coming out of it. Is this normal? Should any air get through the bov under non boost cond.? Of course when you get under boost you have no vacum to open the bov and it will only open when the t/p is closed. Hell, it could be working and just dose not pop off real loud...who knows? Although it did before.
Air going through the valve with no boost is normal since engine vacuum is holding it open. The turbos are still moving air but not enough for positive manifold pressure.
 
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