Jump to content

PSE - valves & RPMs


tob_today

Recommended Posts

My 987.1 RS60 came with factory Porsche Sports Exhaust. I believe this was tweaked slightly over regular 987.1 PSE but assume not significantly.

When turning PSE on via dash switch (to open valves) the exhaust sounds great at low RPMs and high RPMs, however between 2.5k and 4k it seems to become more muted. There is also a slight buzzing sound from exhaust at around these RPM points.

It's as if the car is muting the exhaust sound between this rev range by adjusting the valves. I know Porsche did this with early 996.1 and more recent cars, something about reducing drive-by noise, which lots of people like to disable. But wan't aware they did for this era of cars. I would expect the the dash switch to simply open / close the valves without additional RPM-based behaviours, which would be my preference. 

Anyone notice anything similar? Is this a known behavior with 987.1 PSE systems? Or maybe it's specific to mine? 

Link to comment
Share on other sites

I ve heard of it on American cars but I didn’t think the European ones did it. I ve been out for a drive with Bally off the forum when he had his RS60 and it sounded epic all the time. I know there is a additional bit of kit you can buy to over ride the rpm thing but I imagine you could probably get it turned off at a specialist.

I had the factory PSE on my 987.2 and it was either open or closed, same on my current 981.

Link to comment
Share on other sites

I have Balley’s RS60 and haven’t noticed what you are describing. The dash switch operates 2 solenoids that just open and close flaps on the exhaust. I wonder if the buzzing noise is the flaps rattling about on their pivots. Mine did that before I fixed them but was only audible at very low rpm.

A short clip from my car running with flaps open! More on YouTube if you’re interested.

 

Link to comment
Share on other sites

I have never known for sure if its a thing on UK cars - but I know that on 911 in germany there was a regular hack to prevent the "social mode" - and that police learned to look for the connections being loose.

Some discussions on PH re 996 - again - a bit vague - but i have heard it cuts off around 30 mph ...

https://www.pistonheads.com/gassing/topic.asp?h=0&f=48&t=834498

Link to comment
Share on other sites

Thanks for replies. My car is currently at my specialist and they confirmed the ECU is manipulating the valves at certain speeds / RPMs. This is also audible with a very slight buzzing as solenoids operate to close / open the valves

I've done more research and found plenty of forum posts on US and also UK sites for both 987's and 997's confirming this is intended behaviour designed at factory, assumed for noise regulations in some countries. Seems it's possible to override either with custom switch or Cargraphics have kit solution. Apparently it's not possible to override with factory buttons without some kind of software reprogramming.

Switch solution: https://www.planet-9.com/threads/manual-overide-of-factory-pse.33519/

Kit solution: https://www.cargraphic.de/en/your-vehicle/for-porsche/for-boxster/for-9871/for-34l-s/exhaust-systems-and-components-for-porsche-9871-boxster-s-34l/cargraphic-valves-control-unit-for-porsche-boxster-9871-s-34l/

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...