Z4 3.0 Sound generator

[npower]

How many of u are aware of this? All 3l models have what is known as a sound/acoustic generator which consists of a tube from the air intake. This tube is connected to a hole on the passenger side firewall. The purpose of it is to transmit induction sound into the cabin.
There are two pieces of foam inside this tube- one on the intake side and one on the firewall side.
Now here is where it becomes interesting: u can remove one or both pieces of foam to increase the volume of the induction sound.
Its an easy job to pull out the tube, remove the foam and reinstall.
I've removed one piece of foam and the sound above 4000 is impressive! More of a deep bellowing roar!

Anyone else tried it or wants to try it?:joy:

 

[AdiS]

You can also retrofit it to other z4s. Some Germans have even managed to retrofit it to e46s.

 

[Fraser]

Why not in the 2.5.
Any pics?

 

[npower]

Why not in the 2.5.
Any pics?

Have a look at ffg link. Really informative.
http://www.zpost.com/forums/showthread.php?t=63037

 

[Turbo6]

On the one hand its kinda cool that you get the induction noise channelled into the cabin which could also act as an amazing stimulant for the lady (or guy :biglol occupying the passenger seat!

But on another hand, its kinda silly because usually you want some from of cold/forced induction from the low front of the vehicle all channelled into the intake. Now you have some induction being scooped from the cockpit too in aid of some enhanced induction noise but it makes sense that some induction speed would be lost as a result.

Just sounds all vtech to me!:blab:

 

[npower]

There's actualy an air tight flexible membrane between the induction system and the sound tube. No induction flow is lost. The membrane acts like a eardrum and the tube as a middle ear channel.

Thought I'd share that completely useless bit of info:rollsmile:

 

[AdiS]

There's actualy an air tight flexible membrane between the induction system and the sound tube. No induction flow is lost. The membrane acts like a eardrum and the tube as a middle ear channel.

Thought I'd share that completely useless bit of info:rollsmile:

No its actually quite relevant, because i also wondered about this when I first read about it. It was confusing because i knew they wouldn't allow unfiltered air into the engine.

 

[Turbo6]

There's actualy an air tight flexible membrane between the induction system and the sound tube. No induction flow is lost. The membrane acts like a eardrum and the tube as a middle ear channel.

Thought I'd share that completely useless bit of info:rollsmile:

No its actually quite relevant, because i also wondered about this when I first read about it. It was confusing because i knew they wouldn't allow unfiltered air into the engine.

Okay so I wasn't the only one! :rollsmile:

So what you're saying is, no induction air is sucked in from the cabin and no forced induction is lost. Doesn't make sense to me yet but I will study the sketches and blogs for what its worth. I wonder though, as speed increases in real road circumstances, surely the car without the mod will gain from the more efficient induction. Then again the gain is probably so negligible you wont even notice

 

[npower]

Like I said: the membrane is airtight. It is flexible and transmits induction sound by resonating like a speaker.

 

[Kyle]

Watch people run their induction pipes straight into the car :fencelook:

 

[MikeR]

:fencelook: strange idea

 

[Fordkoppie]

Also known as ISE (induction sound enhancer)

Most [sporty]cars of late have it. I personally like it, because unlike the fake sound generated by the audio system in the e60 M5, this is still real sound - only amplified and if you dont like it, you can always unplug the tube.