My Greddy Type RS is whistling. How to fix it? Hard or Soft?

[kmoore]

Guys I know, i know another bov adjusting question. I'm sorry but i have searched about this specific topic and all i get is the type-s bov. So here's my situation, i got my type-rs about a couple weeks ago and i have still have been trying to get it perfect. When i rev it in neutral at about 3000-3500 rpm i hear this long whistling noise. Does this mean i need to adjust it softer or harder? Thanks

 

[Dragon TalonTsi]

Play around with it, you will have to find the "sweet spot" for your particular car and setup.... it is not the same with each one. That is why they call it adjustable.... you'll figure it out through trial and error.... I have the same one, and mine is in the middle almost, and it does affect the sound too...

 

[kmoore]

So do you think i should adjust it soft or hard? I know it's not supposed to whistle that is why i am asking

 

[PieEyedPiper]

Why are your free-revving your engine to 3500RPM?

But lets think about your issue for a moment.

Q. Why is it whistling?
A. Because the difference in pressure created by letting off the throttle at 3500RPM opens the valve on the BOV enough to let some air escape/enter and creates an audible noise.

Q. How do I avoid this whistling?
A. Stop the valve from opening prematurely; thus closing the tiny gap in the valve's seal that is creating our whistle.

I think you probably see where this is going..

 

[greengoblin]

Tighten it up some.

 

[donmagicjuan]

First of all, are you sure the whistling is coming from the BOV? It could just as easily be a leak somewhere else in your intake system. If it is the valve, however, it doesn't matter if it's opening when you're free revving your engine anyway, because you're not building any boost. In fact, you're at a vacuum, which would explain why the valve is partly open. When you are under boost, the vacuum line from your intake manifold is applying this boost pressure to the top of the BOV diaphragm, which assists the spring in holding the valve closed. You should be able to adjust the valve almost to the full soft position and still not have any concerns about it leaking under boost. I have the same valve adjusted almost fully soft, and I run 26 pounds of boost with no issues to speak of.

 

[kmoore]

I just can't really hear it on the road to adjust it so i thought if i had someone rev the engine up a little bit i could stick my head under there and listen to it more closely. Thanks a lot for the help. When i first got it and i put it in i didn't touch a thing and i was boosting to 12 psi quicker then when i started to tighten it up some so i think i will try to start over with the whole adjusting thing. How do i get the adjustment back to how it came in the box? From what i understand it was at full at full soft right out of the box. If i loosen it up all the way will that adjustment screw eventually come out? Is this a bad thing if it comes out or can i just screw it right back in? Thanks again for the help

 

[kmoore]

And yes i am 100% sure it is coming from the blow off valve.

 

[donmagicjuan]

Just loosen it until the stud gets all wobbly, and then tighten it until you feel it come into contact with the spring. I believe that it's captive, because I've never had it come out of the hole on me, so I wouldn't worry too much about it.

 

[kmoore]

How do you know if it is adjusted too soft?

 

[donmagicjuan]

As I said, it shouldn't leak any boost even at the softest setting.

 

[kmoore]

So i guess it's better to be soft than it is to be hard? Thanks for your help

 

[donmagicjuan]

So i guess it's better to be soft than it is to be hard? Thanks for your help

As long as it's not leaking boost (it shouldn't), then yes. A stiffer setting will slow down the turbine speed between shifts more than a softer setting. You want the turbine to remain spinning as fast as possible during this period to minimize lag after shifting. In extreme cases, an overly stiff setting can cause compressor surge, which pretty much negates the purpose of having a BOV in the first place.

 

[kmoore]

Alright, thanks a lot. But, i am still concerned though, because i set it to the softest setting and maybe turned it about 1 1/2 turns to the "hard" side, and it is still whisteling. What i mean is when i am in first gear and roll just a little bit and i rev it just a little bit (about 1000 rpm maybe) it whistles faintly. Is it supposed to do this? Does your Type-RS do this? Is it hurting anything? Thanks for sticking with me on my question donmagicjuan. I appreciate it

 

[quiksilver38]

my greddy rs alway did the two little high pitch noise after every pressure release. isn't that what they're suppost to do? so you can tell you got a real greddy not a knock off?

 

[kmoore]

Yeah, that's kind of what i'm talking about. Just an example of what i mean: Like, when i am pulling into my garage (which i really slow...duh) and i give it a little gas and release i hear this high pitched "eeeeee". (Best i could do). So i guess if your's does that then it's alright? Anybody elses do this?

 

[quiksilver38]

its more like two tones like the first one more loud then the second one right after a little less loud like skreeches

 

[kevint427]

aight check it, A.) that sound is not how you identify a "real" GReddy compared to a knock off one. In reality 75% of the knock off's are the real ones. Differant stickers on top create the illusion it is better. After working for a few big companies I have learned a lot of stuff is the same stuff. EX: I have a "knock off" type rs that does the faint hissing sound after boost ends and vacuum begins. if you set it a little harder it will not make the sound anymore. however like has bene posted, if you set it too hard you will defeat the purpose of a bov altogether through compressor surge. to dial your bov in and get rid of the sound, sit at the front of your car with the engine running. pop the throttle body ever so gently and listen for the sound. tighten it about a half turn untill it disapears. you want it to be at the point of not losing boost and not having compressor surge. now B.) i had to write the letter b.) because when i got done typing i realized i used an a.) ! hope this helps in some way.

 

[kmoore]

aight check it, A.) that sound is not how you identify a "real" GReddy compared to a knock off one. In reality 75% of the knock off's are the real ones. Differant stickers on top create the illusion it is better. After working for a few big companies I have learned a lot of stuff is the same stuff. EX: I have a "knock off" type rs that does the faint hissing sound after boost ends and vacuum begins. if you set it a little harder it will not make the sound anymore. however like has bene posted, if you set it too hard you will defeat the purpose of a bov altogether through compressor surge. to dial your bov in and get rid of the sound, sit at the front of your car with the engine running. pop the throttle body ever so gently and listen for the sound. tighten it about a half turn untill it disapears. you want it to be at the point of not losing boost and not having compressor surge. now B.) i had to write the letter b.) because when i got done typing i realized i used an a.) ! hope this helps in some way.

So what you are saying is that, that is not good that it is doing that faint whistling noise when i am rolling really, really slow? And i should tighen it so that it goes away. Thanks for the info

 

[donmagicjuan]

So what you are saying is that, that is not good that it is doing that faint whistling noise when i am rolling really, really slow? And i should tighen it so that it goes away. Thanks for the info

Honestly, if it holds shut when you do a boost leak test, then you have nothing to worry about. I think mine makes a faint whistle noise after free-revving as well, so I wouldn't obsess over it. Remember, with a recirculated valve, the only time it absolutely needs to be shut is under boost. For those other times when it could be open, the air going through the opening is already filtered and metered, so you're not risking any damage to the engine or less than optimal mixtures.

 

[kmoore]

yeah, i never thought of that. I don't know if this matters but when i am building boost up my AFTERMARKET boost gauge kind of wobbles up to about 10 psi. It's weird because i build boost and power just fine but the needle on my boost gauge kind of wobbles up to about 10psi like i said. I don't know if this could be a sign of a boost leak or what but maybe this is why my BOV kind of whistles? Thanks for all of your guys help

 

[donmagicjuan]

Have you done a boost leak test? If you have, and the results are satisfactory, check the lines running to your boost gage for any kinks or obstructions. If everything looks clear, you could just have a wacky gage. I don't personally have a mechanical gage, but the one's I've seen didn't wobble as you describe. I'm probably not the best person to help you troubleshoot a faulty gage, though.

 

[MyBeatGSX]

Listen, you're all making this too complicated. This is very simple. The whistle is completely normal. Put a 1G BOV on hard pipes and neutral rev it and it does the same thing. ITS NORMAL! It will do it while decelerating as well. You don't even have to rev that high to get it, I can just make a quick jab at the gas and get it when I let off.

Adjust it full soft and call it a day. Mine doesn't leak one tiny bit at 25psi on FULL soft.

 

[slipstream808]

Mine whistles the EXACT same way when I free rev it to 3500-4000 RPM's. Heck, when I let off the throttle sometimes in 3rd or 4th it'll whistle until i put it in neutral or get back on the throttle. Still holds boost just fine though. A boost leak test will tell you all you need to know. Just tighten it enough so that it holds the desired boost.

 

[mieszkoj]

Hi.

I thought the whistle soudn is the signature sound of greddy.