Stock BOV issues

[GTSPECB STI]

I can guarantee you it will change!

[Jimmy S]

If you need to offload the Zerosports pipe Dave... just to get rid of the excessive noise, you know who to call!

[GTSPECB STI]

If you need to offload the Zerosports pipe Dave... just to get rid of the excessive noise, you know who to call!

just LOL that is all

[Jimmy S]

If you need to offload the Zerosports pipe Dave... just to get rid of the excessive noise, you know who to call!

just LOL that is all

hahahah... you're the one complaining about the "excessive noise"

[UrbanGTB]

Just to be a smart arse I thought I would say this. So there is nothing wrong with the BOV but with what your *think* of it? Doesn't sound like anything wrong with your BOV LOL

[subnub]

The noise would obviously be from the air rushing in to the intake, most likely causing some turbulence, and not being muffled from the intake. That's already been established... the factory stuff is restrictive I presume because it's cheaper and easier to control noise emissions by restriction rather than by expansion chambers or whatever... so how do we address that other than putting the restrictive stock bits back on? I have no idea, hahaha - but here's a few possibly ridiculous ideas you could look into if you're keen!

1. I'm not 100% sure about the Liberty but generally the return pipe joins to the intake pipework at a 90° angle. You might be able to reduce turbulence by angling the return line in such a way that the recirculated gases enter the intake *with* the flow, rather than across it.

2. The air would be coming out at a fairly high speed/pressure. This might be a stupid suggestion, but one way to muffle that noise might be to use a container (a swirl pot for example, something with a bit of capacity) somewhere along the return line. The thinking here is that when the BOV opens the escaping gases would pressurise the container and then slowly equalise with the intake.

3. This might be a stretch, but I guess it's feasible that you might be hearing turbulence at the BOV end of the return line. When air enters the BOV it normally has to make a pretty sharp turn, and some BOV designs mean the air has to go around part of the BOV mechanism which wouldn't help noise. #2 above might help to reduce the noise in that sense too.

4. I have no idea about side-effects but maybe having the recirculated air re-enter the intake closer to the turbo (instead of immediately behind the AFM) could help?

Someone with a bit of knowledge in fluid dynamics or whatever might be able to offer more insight but the above fits with my limited understand of things

[cpitts]

Subnub is accurate in what he's saying. But the easiest translation of it is to put the resonator back on. It's exactly there to absorb these resonant frequencies (air pulses, etc) that flow back up the intake.

In all honestly, you'll probably notice negligible performance difference putting it back on, the hole is so tiny.

The other option is to put sound deadener inside the guard panel where the reso hole is (but that's a bit severe).

Are you sure the noise is outside the car and not just something you're hearing in the cabin? The dump and engine noise does tend to be louder in the car than outside.

The other option is to just sound deaden the car cabin then you don't get annoyed with the sound. If you're not getting pulled up for it then the cops clearly aren't hassled by the noise, it's just you (as has been cheekily pointed out).

[CheesyMong]

Just the end of the intake pipe to the AFM itself. Is anyone else suffering from this same issue once they have done similar mods. Dense air is great but ricer bov sounds are not.

Same as u Dave, along with the good ol backfire crackle from the hitechs when you back of the accelerator when changing gears

[GTSPECB STI]

thanks for the replys on the subject and I think we are all clear on why it happens. Now I just need to source another milk container as I threw the last one away.

[cpitts]

Same as u Dave, along with the good ol backfire crackle from the hitechs when you back of the accelerator when changing gears

Backfire should be overfuelling, that should be corrected with the tune......

Unless the ECU spark cuts on lift-off and runs some fuel through to cool things down. That's a bit illegal though and insane for emissions regs.

[GTSPECB STI]

Just the end of the intake pipe to the AFM itself. Is anyone else suffering from this same issue once they have done similar mods. Dense air is great but ricer bov sounds are not.

Same as u Dave, along with the good ol backfire crackle from the hitechs when you back of the accelerator when changing gears

a get a tiny amount of crackle in certain conditions but no backfiring really. Sean was pretty careful in the tune for last sort of fueling issue.

[CheesyMong]

Just the end of the intake pipe to the AFM itself. Is anyone else suffering from this same issue once they have done similar mods. Dense air is great but ricer bov sounds are not.

Same as u Dave, along with the good ol backfire crackle from the hitechs when you back of the accelerator when changing gears

a get a tiny amount of crackle in certain conditions but no backfiring really. Sean was pretty careful in the tune for last sort of fueling issue.

Backfire was probally the wrong term it is more of a crackle, it is not a bang noise just a gurgle...if that makes sense

[cpitts]

I get crackle sounds with just the gutted mufflers, let alone anything else.

[vitagen]

i get the same prob too after installing an apexi power intake kit and new mufflers

i can really hear the turbo spool and quite a loud bov noise eventhough my gfb bov is set to full plumback

i think its just normal

sounds pretty cool though!