D3 Bi turbo exhaust - F31

raw · Post by **raw** » Wed Jan 24, 2018 9:43 pm

Exhaust sometimes has nice growl and other times not. Assume growl is when car doing DPF clean?? The alpina exhaust seems a waste in terms of sound on the D3 unless I am missing something and wondering if the sporty growl you get during DPF is possible all the time if you want it?
Any one know ?

Thanks

ali · Post by **ali** » Thu Jan 25, 2018 12:39 am

Earlier cars like my B3 have a bitterfly valve in one exhaust port that opens and closes depending on throttle position.
If cruising quietly below 2500 rpm only one exhaust outlet is used After 3k rpm the other one opens up and it sounds a lot more menacing.
The Akrapovich system fitted to yours may well have similar valves