I've been curious to understand the differences between the standard and Competition package exhaust. The S58 technical manual provided me the answer.
https://www.bimmerpost.com/goodiesfo...S58-Engine.pdf
In short, aside from the black exhaust tips, there are minimal mechanical differences between the standard and sport exhaust. There are however functional differences in the exhaust gas flow path length that should make the sport exhaust louder. I've annotated the respective figures to show these differences in the attached image.
Specifically, the sport exhaust has a more restrictive flow path through the muffler when the bypass valve is fully closed. Ironically (if only slightly), the sport exhaust is probably capable of being slightly quieter when the valve is closed.
To compensate for this increase in back pressure through the fully muffled path, the sport exhaust valve tuning modulates the valve position more precisely, e.g. for intermediate loads when in "quiet mode" to optimize back-pressure for fuel economy and/or performance. The tech manual mentions this:
Quote:
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In contrast with the exhaust flaps on the standard exhaust system, the exhaust flaps of the M Sport exhaust system can adopt intermediate positions. Therefore, it is possible for the exhaust flaps to be continuously variably adjusted to any position.
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Whereas the standard exhaust valve can either be fully open or fully closed. Sport exhaust also gets a different augmented (fake) sound program.
This may have already been posted. If so, apologize.