I have the mufflers off the car and am getting ready to do the "Gundo hack" bypass connecting 2" stainless pipe between inlet/outlet pipes on the stock 997.1 S mufflers. I read that this mod was originally done using 1" stainless versus 2" stainless. The car is LOUD without the mufflers and this got me to thinking that I might be happier using the 1" pipe v.s. 2" pipe. I am intersted primarily in TONE and not in LOUDNESS. Anyone done this mod using the 1" stainless pipe or heard a car with the 1" pipe ? I read that this mod was originated by Darin Fister ( fisterd on Rennlist) and he used the 1" pipe bypass. I have heard several sound clips using the 2" pipe bypass and they do sound a bit loud, at least to my ear.

Thanks for your responses.................

 

2" isnt "loud" very mild... ive done 2" on both cars...

997.1 and 997.2

sounds like PSE but louder above 5k rpm

 

I have 2" from FisterD. Not too loud at all!

 

Thanks for the responses. The welding shop will install the 1.5" stainless pipe bypass on Monday. I feel this will give me the sound that I am looking for and closest to the PSE open exhaust sound.

 

Let us know how it turns out.

 

I'm planning on doing the 2" next weekend...

 

I am very interested in this mod. If you guys could post up some sound clips, that would great.

 

This is my 997.1 3.6 with 2" cross over.

http://www.youtube.com/watch?v=Vf0NpWNAj78

Best

Matt

 

FYI, 2" will do about 103.5 dB from 6 ft behind the car (at 7000 RPM)

 

Can someone please post a pic of the hacked side, so iI can show my shop what it is supposed to look like when finished. Thanks
Stan

 

Here you go. I've done both - the 1" will have a higher pitch, the 2" will be deeper and louder.

This is what is possible if you add AWE cats to the equation:
View My Video

Here are some pics of the finished hack:

 

Thanks. Looks simple enough. Any warnings, or is it as straight forward as it looks?
Stan

 

Hey Dave - still happy with your 1.5 Gundo hack? Any noise violations from the local authorities? Interested in Vancouver...

 

Your car sounds fantastic!

 

Zeus 993: Yes, i am VERY happy with the 1-5" Gundo hack. No noise violations and NO resonance at cruising speeds. Really comes in throaty upon heavy acceleration and sounds VERY Porschelike versus many of the other aftermarket mufflers............ :-) Have had many complements on the sound by many fellow Porsche Club members and people on the street.