Hi, had my 1999 3.9 for 10 years now and she came to me with the dual Librands Sport exhaust system which is a joyful tune at full chat and overrun popping and banging away. No other modifications to the system and for touring it is plenty loud enough without being too intrusive tbh.
If I had to guess mine is the loud version as I am mutton Geoff and it ticks all my boxes - if you were to order the loud version they have retro fit quieteners they say.
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