dwboston

I agree. I love my NWB A8 - the A8L just seems like overkill for my needs.

MP4.2+6.0

A guess is it is likely “all of the above,” plus more. That is variously, indeed the through bumper trapezoidal exhaust outlets pioneered on D3 W12 had outlandish parts costs. Particularly the separate stainless/chrome trim pieces that screw to bumper cover, on top of the exhaust tips themselves and the valve switching. In addition, a guess is if one looks under one of these plasticrap designs, we may find the exhaust actually terminates on only one side, at least on a lot of motors. That’s how it was for Audi’s in general until mid life of 4.2 when they went to duals. Some had two pipes in parallel, but still only one exhaust path and one overall set of cans. Cost reduction as well as weight. May help on trunk packaging too, a D body major weak point when they botched it on D4 intro. The AdBlue fluid tank for TDI’s competes for the same space, also a reason for the D4 trunk sub par design as well as the way wide fuel door for the diesels w/ the second fill port. Given TDI debacle that had a lot to do with trying to max miles between AdBlue fill ups, finding space for yet bigger tank was likely part of decisions about rear packaging. The tank used to be on the order of 5 gallons IIRC even pre TDI revelations, so not insignificant space wise. And yes, pure electrics have no exhaust by definition, but on a Tesla S design (that Audi would probably die rather than admit need to address) it results in an interesting ground effects lower fascia treatment instead.