Forge BOV flutter

[DSMcamaro]

Just got forge 1G vented BOV from a friend and no matter what I try, it flutters. I was running a crushed 1G that never fluttered. I didn't change anything besides the BOV.

this is what i found the spring rating to be.
Green - 5-15 PSI
Yellow - 15-23 PSI
Blue - 23-30 PSI

I've tried the forged BOV with just the yellow spring, the green with a shim(which I would think would make the most sense for me since my boost will be around 15-19psi) just the green spring, and even the yellow with a shim.
I'm pretty sure its not surging since i used to have surge issues with my dodge mod 1G BOV and this doesn't seem the same. I'm curious as to whether or not the forge BOV always flutters since it has 2 springs. the one springs is really small and soft. I'll post pics of it soon.

 

[DSMcamaro]

this is the little spring I'm talking about. Does the recirculating forge BOV have the same thing?

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this goes over the top of the little spring.

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[CanadianTSi]

I run only the Blue spring in my Recirculated Forge and it doesn't flutter.

 

[DSMcamaro]

I run only the Blue spring in my Recirculated Forge and it doesn't flutter.

Is it designed the same as this one with the little spring in between? Do you think I only here mine because its vented?

 

[daren_p]

Is it designed the same as this one with the little spring in between? Do you think I only here mine because its vented?

No the recirculated version has different internals from what I can see in your posted pics. The recirculated version only uses one spring.

 

[DSMcamaro]

No the recirculated version has different internals from what I can see in your posted pics. The recirculated version only uses one spring.

Thank you! That would make sense to me. I don't see hardly anyone else using this BOV. I think its just normal to flutter like it is.

 

[daren_p]

Flutter is usually caused by spring tension being too high. I would try just a spring (believe green is the lightest) & see if the flutter goes away (sometimes it doesn't take much of a tension change to stop the flutter). Make sure you have a dedicated line just for the BOV & depending on what size vacuum hose your running, you may want to try a larger diameter & see what that does. Other then that, as long as its not turbo surge (when you get surge you'd know it, not just a flutter sound, the whole car will "buck") you'll be fine.

Edit: Forgot to mention, does that valve also have an oring around the piston body for sealing? If so I'd wipe out the old grease & apply some new fresh grease. If the old grease has gone abit hard or sticky, it can be enough to cause flutter.

 

[DSMcamaro]

besides the grease, everything you stated was covered in my original post. I've tried just the green one, and I'm pretty sure its not surging.

 

[linksys42]

I am having a prob with my recently acquired Recirculated forge. I have tried the green spring and the yellow spring, the green spring wasn’t holding boost in 1st gear it would leak boost then all of a sudden hold and shoot up to 14psi so I thru the yellow one in and it stopped but they both made the same sound when releasing between shifts and at low boost/partial throttle release. But I keep on getting this psssshhwhinng it sounds like a 1g bov releasing with a high pitched ring and it doesn’t seem to shift as smoothly, unless I run full boost at every shift then it releases quick? Also at low boost partial throttle it makes a low pitched ring? It this normal or is it compressor surge? Thanks

 

[DSMunknown]

I am having a prob with my recently acquired Recirculated forge. I have tried the green spring and the yellow spring, the green spring wasn't holding boost in 1st gear it would leak boost then all of a sudden hold and shoot up to 14psi so I thru the yellow one in and it stopped but they both made the same sound when releasing between shifts and at low boost/partial throttle release. But I keep on getting this psssshhwhinng it sounds like a 1g bov releasing with a high pitched ring and it doesn't seem to shift as smoothly, unless I run full boost at every shift then it releases quick?

Not to be a pirate or anything, huh?

Try adding one or two more shims. Also try doing a boost leak test. Right now I have three shims installed with the green spring and the Forge RV still won't close properly (probably because there's a boost leak that I am still unable to locate and fix). I am not saying I have a problem with Forge's products. There is another factor in the equation, mainly the boost leak which is keeping my Forge from performing like it's supposed to.

No, you don't need to purchase this kit for more shims. Go down to your local NAPA store or Ace Hardware store and find some regular ol' washers that are the same diameter and same width. There you go, more shims.

 

[linksys42]

Not to be a pirate or anything, huh?

Try adding one or two more shims. Also try doing a boost leak test. Right now I have three shims installed with the green spring and the Forge RV still won't close properly (probably because there's a boost leak that I am still unable to locate and fix). I am not saying I have a problem with Forge's products. There is another factor in the equation, mainly the boost leak which is keeping my Forge from performing like it's supposed to.

No, you don't need to purchase this kit for more shims. Go down to your local NAPA store or Ace Hardware store and find some regular ol' washers that are the same diameter and same width. There you go, more shims.

I wasn't being a pirate, I saw that someone else was having a similar problem so I posted and the last post was like 2 1/2 weeks ago. already added the shims both of them (I already got the kit), did a boost leak test and didn't have one boost leak at all I already fixed the leaks I had before at the TB and injector seals but for some reason when I pressurize the intake track it always leaks into the crankcase not holding boost for very long? Like say if I pressurize it my compressor has got to keep on regulating the air or else it will drop off rather fast. It will go from 20psi down to like 5 in a couple or more seconds; I guess it's because of the intake valves being open. Does anyone else have this similar problem? Thanks for the help

 

[patty AT forge]

This goes for all of our flanged valves: Check the small lock ring that attaches the valve to the flange, if there are two holes that pass ALL THE WAY THROUGH the lock ring contact me and I can send you a redesigned part. The old style is a source of a constant boost leak, minor but still a leak. Since this leak is beneath the piston, and therefore lowers boost below the piston, it can result in a flutter as boost climbs and drop rapidly causing the piston to oscillate.

The metallic sound is normal with our flanged piston valves but will be aggravated if there are leaks (see above!).

With the atmo valve you may need a stiffer helper spring to stop the flutter but check the lock ring first.

http://www.geocities.com/deadlytrap/DSC01179.JPG

 

[DSMcamaro]

Thanks for the reply. Might want to scale down your picture though. I'll check my BOV soon.

 

[daren_p]

Thanks for the reply. Might want to scale down your picture though. So which one is the updated one?

As Patty stated, the two holes that go all the way through the lock ring are the old style, which looks like it would be the one pictured on the right & the new style with the plugged holes is on the left.

I wish this had been figured out when I had my Forge that had to be returned as it had a flutter issue. Other then the flutter, it has defently been my favourite valuve of the 4 I've ran so far. Maybe have to give the "new" Forge another try

 

[DSMcamaro]

Yea, Once i read over the post again, I figured it out. And I do have the old style with the holes all the way through. A+ to forge for going out of there way and finding my thread!

 

[daren_p]

Forge does have amazing customer service, on the list of best companies I've delt with

 

[Empyrials]

i have flutter on mine but it's just that, not surg. So i don't care, .

 

[DSMunknown]

Forge does have amazing customer service, on the list of best companies I've delt with

I'll back up that statement 100%.

 

[Black_Bullet]

This is good to know as I am ordering my forge bpv in a couple weeks, I had gotten a old style forge bov from a friend for free and since I didnt pay nothing for It i just put my darage garage 1g bpv back on for the meantime till I order the new forge recirculated bpv.
Im going to be running 20-21psi so will run the yellow spring and I hope I have no flutter/ surge issues or anything where Id have to change springs, or add shims, hope it will be a straight up install and go about my day ordeal...
Does anyone have any videos or sound clips of how there forge bypass valve ( recirculated ) sounds?

 

[patty AT forge]

21 psi is borderline for the blue spring... it will really depend on how much pressure drop you see from charge pipe to manifold. The more pressure drop the stiffer your spring needs to be to compensate for the differential.

Definitely give the yellow a try first.

 

[DSMcamaro]

Put in the new piece in last night. Still flutters though. I'm assume still that it is simply because of the smaller(looser) spring inside the BOV, but I don't know for sure. Doesn't really bother me anymore to be honest. It's never has been that loud of a flutter. If I have my music up loud enough I don't even here it. Thanks again to forge for sending me the new piece.

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[Black_Bullet]

The flutter could just be the light spring pressure like you said, as long as its not compressor surge I wouldnt worry about it...

BTW some sound clips of the forge would be nice...

 

[patty AT forge]

I should have some stronger secondary springs in stock soon, I will send you one... hopefully that should cure the issue.

 

[DSMcamaro]

Sure, I'll try it out.

 

[Black95TSIawd]

is your MBC tapped into the BOV line? If so, try a direct boost source from the mani without a T and let me know how it goes.