We just completed our new Speedtech 991 Turbo exhaust design last week and took it out today to demo it with the owner. His friend came along with his Ferrari 599. It was misting and foggy with poor visibility, but these cars handled it perfectly. We were lapping like it was a dry day and had a blast! The sound is a little off due to the heavy fog and wet pavement, but you get the idea. I thought some of you might enjoy the video...

 

The 991 seems very tame sounding, your 996 sounds much better. Tough to beet the sound of a Ferrari though. Thanks for sharing.

 

Yea, that's because Porsche went to the 3.8 DFI motor as of the 997.2TT and it's a whole different ballgame in terms of sound volume. The new turbos have an extremely quiet motor now (997.2TT & 991TT).

That 991TT has virtually an identical 3.0 X-Pipe to the 996TT, yet the sound level is not even close. That's the way it is with the new generation of Porsche turbos. They are just really quiet cars by nature. This 3.0 X-Pipe really improved the sound from stock, though.

 

Also, the high dew point with all the moisture in the air deadens the sound of the exhaust. Here is the 991TT vs. the 996TT on a clear, dry day with virtually identical 3.0 X-Pipes -

-991TT-

-996TT-