" And B6 Audi A4 1.8T all come with the twin exit dual back box exhaust
only the quattro models."
If you mean 'cat-back' (i.e., from the catalytic converter, to the rear
of the car), yes. But that's the US; I recall seeing pictures of
European cars that don't have the nice-looking dual outlets, cut into
the rear fascia panel. I think theirs are tucked up under the bumper.
'04 A4 1.8Tq MT-6 w/sweet-looking dual tips
Central NJ USA