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Bing wrote: 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.

Bing wrote: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.