Gary, I would suspect that it will be as loud as the BTG. The K&N unit is a turbo up intake replacement. The fact that there is no silencer involved and a High Flow/low restriction filter unit lends itself to intake noise. The size of the intake up pipe also has a bearing on the amount of noise that it makes. I have heard both the BTG and the AMX1397 (which I run now) and the AMX is louder than the BTG (the up pipe sizing is larger). I believe that the only aftermarket unit available right now that would not be loud is the Air Raid CAI for the GT Turbo. That unit uses the original up pipe (which is where the one of the silencers resides)and the lower half of the OEM airbox so it will not be as loud. I have not heard that system, so its only a guess on my part but that sounds logical. Thats my 2 cents.
Alan
