thanks man. that is a good point; that intake has greatly increased the amount of noises emanating from under the hood, more so than i expected. the growl and whoosh made sense to me, but this little squeal seems strange and i didn't notice it for months. after too much reading on this site, i was worried that squeal was the sound of a looming turbo related failure or something. i figured it wasn't driveline related if it happens in neutral.
it was my factory plastic BPV causing the squeak. i replaced it with a forge one a few months ago, which got rid of the noise.