[Dave92N54]

Originally Posted by 6266N54

Its how the oem side upgraded inlets sound. Its stupid and sounds like there is a balloon in place of the BOV when you slightly let go of the throttle under a low load. When I switched to relocated inlets everything sounds normal and good now.

Hmm... kind of makes sense though. Long silicone tubes, plenty of space and a great material for sound to echo and sound like a balloon lol

[Sav.]

Odd, after I upgraded my inlets, my DVs got louder.

I've been running Turbosmart DV's for over a year. They look nice, and they are solid - completely opposite of that stock plastic trash BMW gives us.. They're working like a dream. If they never made that lovely sound every spirited shift, I would forget they were even there.

Highly recommend.

[iqraceworks]

Originally Posted by 6266N54

Its how the oem side upgraded inlets sound. Its stupid and sounds like there is a balloon in place of the BOV when you slightly let go of the throttle under a low load. When I switched to relocated inlets everything sounds normal and good now.

What doesn't make sense to me is that the air filters and inlets are on the other side of the turbos from the charge pipe and BOV..........are you telling me that the air flowing through the filters and inlets makes a weird sound that transfers through the turbos and all the way to the BOV? That's hard to believe.

[iqraceworks]

Well, I put the new 7psi spring in the Tial BOV last night. It's definitely lighter, it's fully open at idle, which I'm not sure I'm a big fan of....but I can always switch it back to the 10psi spring.

Long story short......same screeching owl/chicken noise when I'm in boost and let off the throttle and the BOV opens. Larger 1/4" ID line, and 7psi spring.....no change at all. Kind of frustrating...it used to sound so good with the stock inlets on the car.

At this point, I guess I will just have to chalk it up as some strange resonance caused by the silicone inlets....I can't think of any other explanation. I guess I will just leave it until I get some different turbos later this summer....probably just put some PR relocated inlets on the car while I do the turbos. From everything I've read, they will get that nice "whooosh" sounds back from the BOV.

[Bimmer_Bro]

Originally Posted by iqraceworks

Well, I put the new 7psi spring in the Tial BOV last night. It's definitely lighter, it's fully open at idle, which I'm not sure I'm a big fan of....but I can always switch it back to the 10psi spring.

Long story short......same screeching owl/chicken noise when I'm in boost and let off the throttle and the BOV opens. Larger 1/4" ID line, and 7psi spring.....no change at all. Kind of frustrating...it used to sound so good with the stock inlets on the car.

At this point, I guess I will just have to chalk it up as some strange resonance caused by the silicone inlets....I can't think of any other explanation. I guess I will just leave it until I get some different turbos later this summer....probably just put some PR relocated inlets on the car while I do the turbos. From everything I've read, they will get that nice "whooosh" sounds back from the BOV.

That's frustrating for sure! I wonder how long till it drives you crazy enough lol.
I run dual forge DVs but I vent them to atmosphere. I wonder if this setup would sound better for you with the inlets? It's a loud whoosh for sure.
Of course you would have to change charge pipes as well.

[iqraceworks]

I just wish I knew what made the noise change.....it just doesn't make any sense, but it seems like it's a very common problem.

If it's a resonance issue.....that noise from the inlets would have to go through the turbos, through the FMIC, down the charge pipe, and out the BOV...hard to believe.

[zomski101]

How are your logs looking after inlet? Any overboosting and/or throttle closure?

[iqraceworks]

Originally Posted by zomski101

How are your logs looking after inlet? Any overboosting and/or throttle closure?

Honestly, I haven't ran any logs. The car runs like a champ, it really doesn't feel any different than when it had the stock inlets.....it's just got that funny high pitched parrot noise to it now.

Even at mid throttle....low boost situations, letting off the throttle gets you that high pitched squeal where before it would get you a soft "whoosh" sound. Very odd indeed.

[zomski101]

Originally Posted by iqraceworks

Honestly, I haven't ran any logs. The car runs like a champ, it really doesn't feel any different than when it had the stock inlets.....it's just got that funny high pitched parrot noise to it now.

Even at mid throttle....low boost situations, letting off the throttle gets you that high pitched squeal where before it would get you a soft "whoosh" sound. Very odd indeed.

If you still have the stock intake, try putting that on to limit the amount of air going through.

[iqraceworks]

Originally Posted by zomski101

If you still have the stock intake, try putting that on to limit the amount of air going through.

Not sure I want to go through all of that trouble.....

[stewbets]

Originally Posted by iqraceworks

Honestly, I haven't ran any logs.

Originally Posted by iqraceworks

Not sure I want to go through all of that trouble.....

You've been updating three different threads for the past week and half, but haven't even bothered to get a log? And swapping in the stock intake for testing is too much trouble? You don't think this scenario is a little strange?

Anyhow, I noticed all the sounds get louder when I upgraded my inlets, but nothing that I'd consider a bad sound. I do think swapping in the stock intake is not a bad idea to try. It makes sense to me that your noise could be coming from your DCI when the BOV dumps since they're connected to the inlets. The stock intake could provide more baffling or change the resonant frequency.

[iqraceworks]

I ran a log last night....no overboosting or any other issues. If anything, the turbos are starting to get worn and aren't able to hit the 21psi target towards the upper rpm range. The log looks just like it did with my stock inlets....no change.

I've searched tons of threads on people who have had this same problem (and yes, I replied in some of those threads)...with the same sound as posted in the video I linked. Everyone had a Tial BOV that sounded great with stock inlets, and then they went to silicone inlets and they all got that high pitched screeching parrot noise. I have not seen one "fix" for this.

At this point since I know I'm going to need new turbos eventually, I'm just going to leave it the way it is, and install relocated inlets when I do new turbos. Everything I've read says that's the only real "fix". It's something about the soft silicone inlets, not sure what though.

I don't want to try to track down my old intake and mess with installing it again just to see what happens....it's not worth my time.

[isoFLXX]

Same thing has happened to me, I upgraded to pure stage 2 DD with vrsf stock side 2inch inlets with BMS oil catch can and been having this strange issue with the Tial BOV. Sounds like flutter with a lighter spring and like a parrot too with the stock 10psi spring. Springs I have tried are the unpainted 10psi and black 6psi spring which did not fix the issue. Switching to the OEM DV’s did fix it but again I’m not sure what’s up with the tial, on another note it also did the same noise with a synapse BOV which is similar to the HKS so beats me. I been chasing this for some months too.

[iqraceworks]

Here is a log I did yesterday on the way to work.....6th gear at 70mph and then slowly getting into the throttle. I wanted to get a log of the BOV starting to flutter with that 7psi spring in it. Like you said, it doesn't flutter with the 10psi spring in it. It looks like the WGDC starts jumping all over the place when the BOV valve starts to flutter....I'm assuming this is caused by the pressure reverberation from the BOV fluttering??

https://datazap.me/u/iqraceworks/log...og=0&data=3-19

[Bimmer_Bro]

Originally Posted by iqraceworks

I ran a log last night....no overboosting or any other issues. If anything, the turbos are starting to get worn and aren't able to hit the 21psi target towards the upper rpm range. The log looks just like it did with my stock inlets....no change.

Slightly off topic but I saw in another thread you are still running the stock map sensor. You are not going hit over 21psi or even see if you are over boosting or not when you are at the absolute limit of the sensor. The ecu with the 2.5 bar sensor can only read up to 21 psi... so you are not going to see higher then that on the logs. 3.5 bar sensors are cheap. I would be running one now even before you switch to better turbos. You want at least 2 psi of headroom with the map sensor.

[iqraceworks]

Here is a short video I did showing how the BOV responds with the 7psi spring in it. As you can see, it's open at idle...the spring really should be heavier. You can hear a little bit of that hoot owl type noise when it dumps, it's much louder when you are on the throttle and have a good amount of boost.

Even though the noise gets much worse with the 10psi spring....I'm probably going to put it back in. The slightly less annoying hooting noise from the 7psi spring isn't worth the open idle BOV position and the fluttering I get.

https://youtube.com/shorts/Dn3QYym1rYs?feature=share

[iqraceworks]

Originally Posted by Bimmer_Bro

Slightly off topic but I saw in another thread you are still running the stock map sensor. You are not going hit over 21psi or even see if you are over boosting or not when you are at the absolute limit of the sensor. The ecu with the 2.5 bar sensor can only read up to 21 psi... so you are not going to see higher then that on the logs. 3.5 bar sensors are cheap. I would be running one now even before you switch to better turbos. You want at least 2 psi of headroom with the map sensor.

I have a 3.5 tmap sensor I'm going to install when I put my new RB turbos on. I hit 21si sometimes with the V5 E40 map I'm running, but it doesn't seem to cause any issues. Lots of people run that MHD map with the stock tmap with no issues. I think it's right on the edge of what the stock tmap car handle.

As far as that crazy hooting noise from the BOV..it does it even at low boost levels.

[isoFLXX]

Originally Posted by iqraceworks

Here is a short video I did showing how the BOV responds with the 7psi spring in it. As you can see, it's open at idle...the spring really should be heavier. You can hear a little bit of that hoot owl type noise when it dumps, it's much louder when you are on the throttle and have a good amount of boost.

Even though the noise gets much worse with the 10psi spring....I'm probably going to put it back in. The slightly less annoying hooting noise from the 7psi spring isn't worth the open idle BOV position and the fluttering I get.

https://youtube.com/shorts/Dn3QYym1rYs?feature=share

Mine does the exact same noise and when I cruise on light throttle it begins to hoot hoot hoot hoot until I let off the pedal. I did upgrade to the 3.5 Tmap sensor and also noticed the WGDC fluctuations. This literally occurred after my turbo upgrade and even took it to the shop who installed my turbos and they didn't have a clue and instead tapped my manifold and removed my bms BOV kit adapter and charged me a hefty penny to not fix my issue. They said they installed a turbo smart BOV and the same issue occurred so I'm not sure what's going on anymore. I also changed my boost solenoids yesterday and still the issue is present.