My experience with non-PSE "S" exhaust is that it just makes it sound like it is always in the "loud position". So based on that, how the valves work, and the details drcollie provided earlier, you should expect that it will just always sound like it is in the loud position. If you already drive with it in loud mode you just won't have to hit the button anymore.

For those without PSE, note that when you first start your car up in the morning, and the initial few minutes of idle sound much "throatier" and "rough?" That is what you will hear but it will stay in that mode all the time. Sounds great when driving even at low RPM, and excellent on downshifts! (maybe I should get an audio of the sound....)

And remember, the beauty of this little mod is that if you don't like it, takes all of 5-10 minutes to switch it back by un-capping the hose and reconnecting to the valves on the exhaust.

Oh, and I also would appreciate it if someone with PSE exhaust does this mod, they take pics along the way, especially where they differ from what I posted in the DIY. I would like to add them into my OP, or at least link them.

 

I will always sound like the console button is engaged. So why do it.

 

Does anyone know if a different computer flash is utilized after a PSE is installed at the dealer to compensate for less back pressure? Just thought that might relate to the valve plug modification?

 

If you have a Porsche Sports Exhaust installed by the dealer on a car that did not come with it, you will have to have the console button programmed as it interfaces with the air conditioning module and control panel inside the car. If you don't have this re-programmed, then your button will not work. 1 hour shop time is the usual charge. If you don't care about being able to switch it on and off, you can skip the whole button-in-the-console step and the engine vac will control the sound level (on 3.8L S cars, the 3.4 Base cars require plumbing)

There is no engine management software change for a cat back exhaust of any kind, because you are not needing more fuel to run them and hence no performance gains other then maybe a few lbs lighter. The PSE is not a performance upgrade, its a sound upgrade. Bolt it on, and go.

 

Right, drcollie. I posed this as a very simple harmless "mod" akin to some people plugging-up their symposer, or even adding an aftermarket exhaust to enhance or change the SOUND of their 991, not as a performance mod. And I offered this as a DIY simply for those, who like me, have a curiosity about such things -- considering how many threads are started on this forum by owners not quite satisfied with their OEM exhaust and seeking opinions on alternatives I thought this just might satisfy those who are not interested in spending several thousand $$ to retrofit of replace a standard "S" or even PSE exhaust.

 

It was a great thread! I wanted to change the sound without spending a bunch of $ to do it. Performance is not an issue. Thank you again!

 

I replaced the whole cat-back exhaust on my 991S with a TUBI after mucking around with several different options. Not everyone wants to drop $ 4,500 on a cat-back exhaust but I enjoy it every time I start the car and would do it again in a blink. Stock is on the right....

 

Genius!! Took me 20 minutes just because I couldn't get a hold of the hose. I had to somehow get 2 hands in the tight space and hold it with a wrench in order to cap the hose. FIY, if you get the same vacuum hose assortment as the OP, only the biggest one fits. The rest are too small I think.

I love the new sound it produces! Definitely throatier than stock. Best $2 mod and it can be reversed so easily!

Thank you!! Saved/Delayed me $2000-3000 in getting either the PSE installed or AWE.

 

Did the car throw a code or check engine light?

 

If you cap the vacuum line after disconnecting you shouldn't receive any warning messages. If you don't you get a "Coolant System Failure" warning. Non-critical yellow message, not red. This is a non-critical component meaning it really doesn't matter at all to the rest of the car whether your valves are working or not. As drcollie and others have stated prior the ability to control the valves is purely for sound control and nothing more. The car will throw a warning simply because it senses the control stopped working -- not because performance or anything else is effected.

Hope that helps.

 

Glad you found the DIY useful! Fun, huh?

If you are having trouble holding the end of the hose to put the cap on, you can use a pair of long-handled pliers or tongs, something like that.

 

Thanks for the quick response. I gathered as much since the car seems to do everything but dishes that there would be some light coming on. I'm gonna try it since I do own an elongated needle nose, but not 2k for a sport exhaust.
Merry Christmas .

 

drove it for about 40 minutes...nothing came up

 

I would love to hear from others if they've figured-out an easier way to
access the drivers-side valve, or the T connector mentioned above....[/QUOTE]

hi!
since this is an old thread, you may have already figured this out.
i was able to remove the driver's side , but took me like 15 minutes just on the driver's side alone trying to figure this out.
i failed the first time because some of the parts around the hose were still hot even after parking it for an hour. so i drove the car on to the rhino ramps and left it over night.
once cold, i just kept working with it until it happened. sorry, no special instructions or tools, just kept forcing by hand and finger in all possible directions.
i also bought the smallest vac caps that they had at autozone and plugged the valve side. im pretty sure it's not required but didn't like the idea of leaving the hole exposed.

thanks for posting this thread btw!!!!!!

i only had 100miles on the car when i did this and it did immediately get louder but didn't hear too much burbles like my awe center pipes on a previous 991 3.4. but now that i have 400 mile on the car, the bubles are getting lot louder to a point where i'm hearing it with the windows rolled up.

anyone know how long it take for the exhaust to fully break-in?

 

Do you have a guess of the size of the vacuum cap that worked for you?