making a 981PSE quieter

[AW10]

I've found other posts on how to make the PSE quieter but I would like to be able to do the opposite - avoid the extra noise created above 4K when the PSE is switched off. Does the PSE, even when switched off, still open the boxes up somewhat as the revs climb?

[AW10]

It's too "boy racer" for me when it gets noisy from 4K upwards under load. Was in a slow moving queue today in a 30 zone behind a tractor cutting verges within a village, patiently waited my turn and then accelerated hard to make it a short overtake. I think I made a small girl cry with the sudden noise seemingly coming from nowhere - certainly her Mum was shooting daggers my way. V cringeworthy moment of unnecessary noise that changes in a very non-linear fashion. Might start looking for a used regular system!

[V800MJH]

You want to make it quieter than when you have PSE turned off?

My car is pretty quiet when it's off (which is barely ever) and I'm cruising around.

May be worth checking that your valves are actually opening and closing fully and not seized open a tiny bit the whole time.

[AW10]

The car is quiet when PSE is off up to perhaps 4000 rpm and then it gets much much louder - definitely a non-linear change in the noise.

[bcr5784]

AW10 said:

The car is quiet when PSE is off up to perhaps 4000 rpm and then it gets much much louder - definitely a non-linear change in the noise.

The standard exhaust does get louder in a non-linear fashion about 4000 too - but I wouldn't describe it as anything like "much much". PSE (off) is almost certain to be louder than the standard system as the rear silencers are quite a bit smaller.

[AW10]

The non-linear change makes me think the PSE is doing something to the noise level even though it's switched off. I'm used to 8K redlines in a V10 M5 and Z4M and their noise levels rises in a pretty much linear fashion.

[AW10]

An update - the actuators for the PSE are vacuum operated. The default mode (when there's no vacuum being applied) is noisy; engine vacuum pulls the actuators closed and routes the exhaust gases the long way round. When a PSE-equipped car is started there's that initial "bark" even when the PSE is switched off (quiet mode) as for a second or two there's no vacuum to close off the noisy exhaust path.

I've used cable ties to tie the actuators closed and the car is noticeably quieter than when in quiet mode. The noise level rises more or less linearly getting a
bit more pronounced above 4K - but nothing like the sudden change experienced without the cable ties. A friend has corroborated this.

So not sure if the PSE is working as intended. One source at a dealer states that in quiet mode the exhaust should always be quiet but that's not what I'm seeing. Any thoughts?

[Malo]

I had PSE retro fitted. When off the car is a little louder than original. When on I get the full works. So my guess is that the pipe work is a larger in the PSE system, hence more noise.