Drone is very subjective! Also, I still don't get why an auto transmission can give drone!? The transmission will only dictate what revs the engine is doing at a given speed. So in theory, the manual will give drone at the same rpm!? Also check that Milltek are not referring to the DSG auto as this has 7 gears and rpm at 50mph will be different to the tip tronic 6sp auto in the V8! Also the V6 and V8 will give the 'drone' resonance at different rpm due to the exhaust pulse rate.
You can kill drone with a bit of science! Search Helmholtz chambers/J pipes.
The only silencers I have on mine are the back boxes! Non res V8 downpipes, mid silencer delete with ECS X pipe, then V8 gutted and straight through-back boxes, BUT, I added 2 Helmholtz chambers to the X pipe to cure the, what I call, 'boom', not drone, not that there was much anyway. Also added remote control valves to shut the in-board tail pipes off further reducing the volume and boom. Loud when I want it to be and OE quiet on the motorway. Adding exhaust wrap to the down pipes reduces the rasp and mellows the tone too.
The OE back boxes have Helmholtz chambers built into the design! The V6 back box is straight through and the V8 boxes have tuned pipes, 3 chambers and a helmholtz chamber. Looking at the design, the V8 boxes look to be possibly restrictive so a performance back box should give more sound and some more horses.
Did have a play with the old OE back boxes, but they were too Fast N Furious, too ricery! Nice loud crackly DSG farts though!
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