[NYBugman1972]

My 2.5" phatboy (magnaflow) is on the loud side, plus you have the webers sucking in air as well. I would imagine that it's comprable to GHL's 3" turbo-back exhaust for 1.8t's. A set of webers can also be a little loud. In a standard setup, you can hear the fan whistling a bit. Straight cut cam gears will produce a whining, supercharger-esque sound.

There are some exhausts that are set up with two straight-thru mufflers in line with eachother. I'm not sure how much quieter it makes the engine.

Personally, I love the sound of the AC engine. Webers sucking in air, the mechanical sound of the engine itself and the lumpy boxer exhaust note is part of the mystique and personality of these cars.