2004 Cabriolet sports exhaust conversion/hack?

[slaskowski]

My brother (who is the mechanic in the family)  sent me the following video of a person in the UK who converted his 996 stock exhaust with a bypass from the inlet to the outlet pipes.    It claims that it is what Porsche has done with the sports exhaust option that was available on the 996 (though with the Porsche option you can turn it off/on)

 

https://www.yahoo.com/news/simple-exhaust-modification-gives-996-212015583.html

 

I have a 2004 911 Cabriolet and was thinking of doing the mod to my car, though I am a bit concerned that it may be a bit too loud.   As I live in Florida, I try to drive with the top down as much as possible.

 

Two quick questions to the forum:

 

1. Does anyone have any personal experience with the sports exhaust option on their cabriolet?   Specifically do you keep it turned on/off most of the time and does it depend on whether you have drive with the top up/down?
2. Anyone done the hack in the video and are there any gotchas I need to be aware of?

 

I appreciate any feedback.

 

[shark715]

We have an '04 C4S cab with factory installed PSE.  I modified the relay (using the instructions another forum member posted years ago) so that PSE is default on.  I rarely turn it off (top down or top up) unless I'm leaving the house super early in the morning so as not to disturb the neighbors.

 

Just love that sweet music coming from behind us, especially above 3000 rpm, and especially with the top down.

 

Is it too loud?  I would say 98% of the time, no.  I'm under the impression most of the aftermarket systems are louder.  I've been asked many times by other 911 owners what aftermarket system I have as they seem to like what they are hearing and don't realize it's an OEM system.

Edited January 5, 2017 by shark715

[slaskowski]

2 hours ago, shark715 said:

We have an '04 C4S cab with factory installed PSE.  I modified the relay (using the instructions another forum member posted years ago) so that PSE is default on.  I rarely turn it off (top down or top up) unless I'm leaving the house super early in the morning so as not to disturb the neighbors.

 

Just love that sweet music coming from behind us, especially above 3000 rpm, and especially with the top down.

 

Is it too loud?  I would say 98% of the time, no.  I'm under the impression most of the aftermarket systems are louder.  I've been asked many times by other 911 owners what aftermarket system I have as they seem to like what they are hearing and don't realize it's an OEM system.

 

Thanks for the reply!!   I am heavily leaning to getting it done (assuming I can find someone local who I trust to do it).

[318touring]

Do it, got mine done a couple of years ago.  

[judgejon]

I would be careful about this.

Check with your state/county, anonymously of course, about smog regulations.

A factory system would be no problem, but I wonder how the system you contemplate would comply with your local smog regs.

There could be a hefty fine involved, and forced removal of the new mod system.

Does your state/county have an annual inspection requirement along with annual vehicle registration?

If you are good to go re the regs, then why not?  I don't believe the cut-out would effect the maf, etc, or obd computer.

Hypothetically, some people, having owned older air cooled 911's, in county's that do not have annual inspection requirements, just might have been tempted to remove the cat and put on a "test tube" with a nice sounding borla exhaust system.  Just sayin....

[rockhouse66]

The mod you are describing is the same as the Fister mod.  You can buy modified mufflers from Fister outright or exchange, or it can be done by a muffler shop.  Many owners have done this and report satisfaction with the sound.

 

I don't think this is the same as the PSE exhaust routing, which actually has two inlets and one of them bypasses a portion of the muffler internal baffling.