Sound Generator Modification

[williams_Z4]

Hi

I am new to BMW's and have just bought a 2.0 2008 Z4 and was wondering if there was a solution such as this to increasing the sound of my engine?

[Ozie]

I think if you took the end tube off completely then you would lose a lt of noise from the cabin, but the engine would be noisier outside ? Not sure if that would affect the efficiency of th inlet into the engine though.

I've done sound generator retrofit to 2.2. It's same as in 2.5.

Has anyone tested using sound generator without connecting it to firewall? Then all sounds from sg would come out next to engine

[alpwhite46]

Hey guys,

I removed the sponge that is closest to the firewall...
Now i was wondering what you did regarding the big sponge that is on the other side?




I can't seem to separate these 2 pieces as it seems it would break, and i can't fetch the sponge out of this

[sk93]

leave that sponge in.. it works to stop any unwanted crud getting into the intake!
Removing either one or both of the other two is all you need

[Bing]

sk93, welcome back

As the originator of this most awesome thread, are you able to repost your pics in your original post ?

[sk93]

Hopefully.. I MAY have the originals someplace, which I will upload again.

however, if I don't, I can always just retake them

[alhattab]

heyy im new here, and i like the post very very much. however the photos seems to be expired. is there a way you could re-post them ?

thanks

[sk93]

I'm retaking the photos as soon as my car turns up..

but welcome to the forum and I'm glad you like the tut.

if I can help you at all whilst we await my car's return, please just say and I'll try

[Z4777]

I tried this mod earlier today on my 07 plate 3.0si coupe. I removed the pipe from the firewall then removed the foam inserted inside it (my foam was the grey type). I then refitted the pipe into the bulkhead and i heard it click into place.
I then took it out for a drive and under hard acceleration it made almost no difference IMO. The only change was an increased whining noise a bit like a supercharger. I decided to pop the foam back in

[si-forks]

I have no foam in my 3.0si 06 and either iam going deaf or its made no different

Sent from my GT-I9100 using Tapatalk 4

[Wildfire]

Does it make that much difference?

When I get my car this Sat I may have a go.

When I test drove the car my gf did remark that the car was quiet and she couldn't tell when we were accelerating.

The exhaust is very quiet. Having said that, I did get the car so that it was also quieter than my other car all round. But then 115dB is an easy target to beat!

[BeemerMad]

Im struggling to get the pipe back in the hole (giggety) for the cabin!

Any help please?

[karwin878]

Promised some photos, so here they are... Sorry it has taken me so long

Note that this is for the N52 engine - so facelift, and mine is a 3.0 which already has the sound generator installed. The M54 sound generator is different ; I do not know if a facelift sound gen will fit into a pre-facelift car. ///Ms do not have a sound generator - arguably the engine itself and the two extra exhausts do that job

All this will do is show you how to find the right bits in the engine to remove the foam. It is NOT necessary to take the whole sound generator assembly out as the initial how-to on this thread indicates, only the ends of the pipe that contains the foam.

This is the sound generator. The large rectangle shows the main body of the part, the second smaller rectangle shows the bit we are interested in, which connects to the firewall bulkhead :



Close up pic from the same angle :



Close up pic from a different angle looking from the front of the car, bulkhead connection circled :



First stage of this mod is to simply pull the bulkhead end away from the firewall. Takes some force but just pulls out. Then twist the tube up towards you and you see this :



The foam will be clearly visible in the hole that is circled. Mine is, of course, not present

The circled bit is important - it is rigid plastic and must be "clipped" back into the metal hole in the firewall. I use quotation marks because there is no set position, just line it up feeling with your fingers and push till you hear it click in. This is the hole in the firewall :



If you want more noise, you need to take the foam out the other end near the engine - this is stage two of this mod. You need to undo the jubilee clip to the right of my finger below (circled in pic 2 above) - quite a long way - and work the tube off. This takes some effort and can result in skinned knuckles.



Your choice whether you remove it completely, cut it down, or not at all. I have cut about 1/3 of it off and then stuck it back in and that's just fine for me. All foam out made my ears bleed and (to my brain) soundedlike I was murdering the engine at 6-7,000 RPM.

Getting this tube back on can be a bit of a PITA - there is a notch in the end of the tube you need to line up with a corresponding 'bump' on the fitting that is attached to the rest of the sound generator. Takes some wiggling and some force too - more skinned knuckles potentially, but worth it. Sorry, no pics of that as I was short on time - but you'll figure it out

I thought about re-posting the OP's text and my pics, but I wouldn't do it that way, and I didn't have time to take the whole assembly off. Hopefully that helps anyone else looking at this thread now the original photos are gone.

Bing, thank you for the pics. Helped me do mine quick and easy!

[Bing]

karwin878, you're very welcome

[NathanZ4C]

Done this mod today

For those who haven't done this yet. I managed to pull the rubber grommet out of the bulkhead when I pulled on the pipe as it was attached to the pipe. I spent about 30 mins trying to get the pipe and grommet back in together. This didn't work. I later realised that the pipe separated from the grommet. I could then put the grommet in first and then pop the pipe back in afterwards which was far easier.