ITT: quiet BOVs/bypass valves
#21
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Originally Posted by MartinezA92
-Not running a BOV is not an option.
If I understand you correctly, this is what someone already said. I'm going to try it in this configuration, and also with it recirculating.
#22
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alright guise.
Is this what I'm looking for? I've seen this mentioned on this forum and just want to confirm.
http://www.034motorsport.com/turboch...n-p-18712.html
I looked on ATP turbo and didn't find anything, so I googled Bosch recirc BOV "710 N", and stumbled on that.
Also read **** about them leaking. I'm going to go out on a limb here and say I won't be seeing anything above 15 psi for a long time.
Opinions/comments/suggestions etc. appreciated.
Is this what I'm looking for? I've seen this mentioned on this forum and just want to confirm.
http://www.034motorsport.com/turboch...n-p-18712.html
I looked on ATP turbo and didn't find anything, so I googled Bosch recirc BOV "710 N", and stumbled on that.
Also read **** about them leaking. I'm going to go out on a limb here and say I won't be seeing anything above 15 psi for a long time.
Opinions/comments/suggestions etc. appreciated.
Last edited by MartinezA92; 04-21-2011 at 12:38 AM.
#23
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alright guise.
Is this what I'm looking for? I've seen this mentioned on this forum and just want to confirm.
http://www.034motorsport.com/turboch...n-p-18712.html
I looked on ATP turbo and didn't find anything, so I googled Bosch recirc BOV "710 N", and stumbled on that.
Also read **** about them leaking. I'm going to go out on a limb here and say I won't be seeing anything above 15 psi for a long time.
Opinions/comments/suggestions etc. appreciated.
Is this what I'm looking for? I've seen this mentioned on this forum and just want to confirm.
http://www.034motorsport.com/turboch...n-p-18712.html
I looked on ATP turbo and didn't find anything, so I googled Bosch recirc BOV "710 N", and stumbled on that.
Also read **** about them leaking. I'm going to go out on a limb here and say I won't be seeing anything above 15 psi for a long time.
Opinions/comments/suggestions etc. appreciated.
#24
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I "figure" because i've researched bovs plus manufacturing is my nature/job/career so i know how to read the blue prints and make heads/tails of whats on there.
Recirculating ones are very simple. Its just 1 piston that opens when in vacuum. You dont really care that its open as the pipe goes to the turbo so either way there is a filter keeping it a clean loop. If you remove the pipe and put a "horn" on the recirculating valve now when vacuum is present the valve is open however its now open to the atmosphere so unless there is a filter on the other end crap can enter through the valve. Vent to atmosphere on the other hand are made to.. well vent to atmosphere. They solve the issue by putting a second piston in that stays closed unless forced open by pressure build up after releasing the gas.
The important part here is that the one piston behaves exactly like the piston in the recirculating valve. Its always open when in vac however the 2nd piston stays closed so unfiltered air cannot enter through the BOV.
#26
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Can someone point out the whistle tip from this page?
http://www.mazdas247.com/forum/showt...lean-HKS-SSQV&
http://www.mazdas247.com/forum/showt...lean-HKS-SSQV&
#27
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The three "fins" in the opening.
I actually have one of the ones Begi sell in my forsale thread Here. If you are interested shoot me a pm and we can work something out.
#30
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I have never seen such a blow off valve as below, unless you're talking about a synchronic with the anti-stall valve, which is basically a check valve. What you may be talking about is a pull type blowoff valve, which don't operate the way you try to explain it. They still only have one piston. The thought is that the boost pressure pushes against the valve to hold it closed for more mad tyte boosts before it leaks, realistically it's just the same as a push type valve plumbed backwards, it hooks to the charge piping on the exhaust side, and exhausts on the boost side.
If you have links to drawings, cut aways, etc. of what you describe as a VTA bov, I'll happily eat crow.
Vent to atmosphere on the other hand are made to.. well vent to atmosphere. They solve the issue by putting a second piston in that stays closed unless forced open by pressure build up after releasing the gas.
The important part here is that the one piston behaves exactly like the piston in the recirculating valve. Its always open when in vac however the 2nd piston stays closed so unfiltered air cannot enter through the BOV.
#33
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LoL and i can take what you say, completely change the wording to completely change the meaning of your sentence and make it sound like you're a complete ******* moron. Stop reading between the lines and do some research on your own dude. Let me get you started. http://tinyurl.com/3s8vlrk
As far as you not knowing the VTA dual piston valves... I just opened my damn valve TODAY stop rewording my sentences just because you have no idea wtf i'm talking about
.
/flame off
Alrighty getting back on topic... the reason why my valve was so quiet is because the 2nd spring was simply too tight so unless i spooled that turbo good, there simply was not enough pressure to open the 2nd piston. Today i took that spring out and replaced it with a softer spring that has just enough force to hold it closed until the turbo starts compressing. At that point i have slight leak which goes away after main valve shuts closed at about 15inhg and up.
Now i can hear it
...kinda whistly though.
As far as you not knowing the VTA dual piston valves... I just opened my damn valve TODAY stop rewording my sentences just because you have no idea wtf i'm talking about
![facepalm](https://www.miataturbo.net/images/smilies/facepalm.gif)
/flame off
Alrighty getting back on topic... the reason why my valve was so quiet is because the 2nd spring was simply too tight so unless i spooled that turbo good, there simply was not enough pressure to open the 2nd piston. Today i took that spring out and replaced it with a softer spring that has just enough force to hold it closed until the turbo starts compressing. At that point i have slight leak which goes away after main valve shuts closed at about 15inhg and up.
Now i can hear it
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#35
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I was gonna suggest finding somebody selling a used one with the crossover pipe and supporting charge pipes... looks like shuiend has exactly whatcha need. Recirc is definitely going to be more expensive though, gotta have cold side charge pipe and intake pipe able attach to the recirc pipe. Recirc would be quieter but you may be able to get away with a vent to atmosphere if you find a way to muffle the sound. Maybe like the hks with the fins out and something over the port. Sock or sponge comes to mind but theres gotta be a better solution.
#36
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A vent to atmosphere blow off valve takes the pressurized air in the charge pipe and releases it into the atmosphere.
A recirculating blow off valve takes the pressurized air from the charge piping and releases it the same way as a vta, but instead of into the open air, it releases it down a pipe back into the intake pipe downstream from the maf/afm, that way all the air in the system is measured.
#39
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I see what you mean then, just use the bosch as a regular bov. Also on the hks you can adjust the bov, looser you make it the less pressure it takes to release the air. tighten it up and the more pressure it requires. If you have it tightened up and it took say 5psi before it would vent you just wouldn't have to worry about it going off at all, and if your boosting over 5psi your blow off valve isn't going to be what gives you away.
#40
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LoL and i can take what you say, completely change the wording to completely change the meaning of your sentence and make it sound like you're a complete ******* moron. Stop reading between the lines and do some research on your own dude. Let me get you started. http://tinyurl.com/3s8vlrk
As far as you not knowing the VTA dual piston valves... I just opened my damn valve TODAY stop rewording my sentences just because you have no idea wtf i'm talking about
.
/flame off
As far as you not knowing the VTA dual piston valves... I just opened my damn valve TODAY stop rewording my sentences just because you have no idea wtf i'm talking about
![facepalm](https://www.miataturbo.net/images/smilies/facepalm.gif)
/flame off
What you're talking about is an add-on that compensates for too little spring mixed with a little hype. I have done the research, designed, and built my own valve based off the cheapest of cheap ebay valves. What that fancy widget does can be accomplished by adjusting spring preload or spring rate so that the valve isn't open at idle.
You're the one that got all huffy, twice, when asked to clarify what you're saying, so I did it for you. Try deep breaths and not assuming everyone's out to get you.
On topic, The ebay RFL I had wasn't all that loud when the trumpet is removed and a straight fitting was used. They're just sprung really softly so they're open at idle and blow off every time you think about lifting the throttle