synonymous

I have the PSE on my C4 GTS and it definitely is a much deeper, fantastic sound when PSE is on, but burble on downshifts or backing off the throttle is pretty much absent. Is this normal? Thanks.

gr1275

It is absent on our '11 "S" as well. The dealer tells me the PSE is okay... One of the reasons I've been considering a change to a SharkWerks cross over.

Gary

Blu311

Cant comment on the PSE but on my gundo hack I get occasional little burbles when backing off the throttle at certain RPMs. It doesn't seem to be consistent though and I would happily take more burbles... does anyone know if adding a center muffler delete would add to the burbles?

92C2Targa#119

Mine is the same. Must be normal

nwGTS

I have PSE and Sharkwerks bypass. It burbles a bit with a cold engine but after it warms up I don't get the burbles. Burbles are just hot, unspent fuel igniting when the fuel hits oxygenated air right? I suppose exploring how to create that would solve your burblelessness.

JAGMAN1

I get burbles regularly with the TechArt exhaust with the klappenauspuff
activated. That's a new German word I just learned. It means valved exhaust. From in the car the burbles don't sound obnoxious and angry. Not sure what they sound like outside.

If I'm coasting down a hill in second or third and I cover the gas pedal with my foot (to let in minute amount of fuel) it will burble the whole way down the hill.

Tcc1999

This was covered a while back (it was a pretty obsure thread). If my swiss-cheese like brain has't totally failed me, it was stated that the initial burble was related to exhaust gases being channeled to warm up, the catalytic convert system. I guess this is why that sound lasts only about 30 seconds.

I have a Sharkwerks bypass and it helps. In California there isn't much that Air Resource Board allows as far as exhaust system mods are concerned (but you don't have pass an inspection until your car is seven years old so there is that). Anyway, it was also discussed quite a while ago, that the exhaust note has silencers built in to meet Swiss (maybe even some other Euro countries as well) noise abatement requirements. So the PSE works as expected, then at a certain speed/RPM is muffled, then kicks back in again. On that same thread I beleive it was also discussed that there is a solenoid switch (or something like that that controls the baffles?) that you can disable so the the PSE will stay on all the time. (By PSE on all the time I mean the automatic muffling system, not the on/off switch in the cabin.)

FWIW, my PSE/Sharkwerks is tame up until about 3K RPMs, gets quiet at about 4K RPMs and kicks back in above 5K or so RPMs.

robh75

This may be a silly question, and mean no offense. But curious as to the appeal of the "burbles?" To me, those sounds are more of a negative rather than a positive.

zirrah

Its a raw, race car like sound. Some love it, others not so much.

robh75

Ah yeah for the track - it is cool to sound like a race car there, if that was the reference here I totally get it. I was assuming there is also preference for this burbliness on street use as well, since I hear these especially from newer Mustangs or other american muscle cars mainly.

Philster

American V8's, given the firing order and longer stroke and longer pipe length, are burble/rumble prone.

The Flat-6 is sort of the short-stroke, oversquare, well-balanced design you want if you're looking to avoid burbles and rumbles. Lol.

Exhaust growl is so important to some brands/buyers, they engineer it in at (seemingly) all costs. American pony and muscle cars get it engineered in, but it's happening in a package that relishes it and can make it happen.

The Porsche market is different. This is a general statement, but Porsche is fine with 'that sounds nice' and 'that sounds sporty'. As for afterrmarket systems, the more elaborate and aggressive ones tend to get good amounts of burble in.

I get mine from glass pack resonators instead of mufflers. .

.

stronbl

Interesting thread on personal preferences ...

I get a few burbles quite often in almost all driving conditions, MY2010 C4S X51 w PSE. But it is a cab so I have the top down a lot which seems to allow me to hear them clearly - even pops and mini backfires in sport plus in mx rpm upshift cases.

Over on the 991 forum there is a thread on this too, but sometime during the 991 design/build Porsche added more symposer sound to the burbles and now the cars do it almost excessively, way too much for many owners. I have to admit, I drove a 991 cab back in August at a Porsche event with the top down and I thought there was too much fake burbles too.

Maybe there will be a new option in the 991.2 to turn off the burbles, I'm sure it will be priced accordingly.

sandwedge

Odd. I have the exact same setup as you and I get plenty of burbles when coming off the throttle. Even a mini burble/pop when up shifting in sport plus going hard at it.

phaphaphooey

I believe you may be incorrect. It is my understanding that only the 997.1 have the speed related cutout. I could be wrong though.

To the OP, get a bypass pipe. Wakes the PSE up.

StormRune

Same as SandWedge. I have PSE and the Sharkwerks bypass I often get burbles when transitioning to off-throttle and occasionally when downshifting at mid-to-lower RPMs. I also sometimes get a "bark" in Sport Plus shifts at higher RPMs under full throttle too (I tend to prefer Sport Plus when in manual mode). It's all a bit different than the V8 burbles though and the sound seems appropriate for our engines to me. In case it has some effect here, I have an in-cockpit switch that keeps the PSE on all of the time when I want it. Maybe the OEM ECU control is lessening the burble effect if you don't have a manual override.