Nick, just keep an eye on your turbo inlet blades. If there is dirt or corrosion, than your K&N isn't doing it's job. I've had a K&N in the stock box for 118k miles and no problems yet on filtration, but I'd like something that would lower my EGTs. Been considering the scotty II. Do the 3's have you drilling the 4" dia. hole? If so, how much more noise?