Curious how much $$ that mod was to perform...TIA.I found out what the problems is -- I took my Treg to a exhaust shop and the problem is in the OEM muffler. I had them replace the rear muffler with a dual Flowmaster exhaust system and WHAMMO it sounds great. I also had them remove the 2 front catalytic converters and straight pipe to the Flowmasters. Picked up major horsepower (not sure how much) and sounds really sweet with no hum or resonance. And for half of the price the Fabspeed set is for sale now on Treg Central. Trick is metric pipe sizing. VW uses a funky size not standard in US so I had them blow it up to 3" -- better air flow anyways. Since the oxygen sensor is in front of the second set of catalytic converters (that I removed) the Treg is smog legal in Cali.
Power to the People!!!