I just made some mod's to my exhaust. Just put in a straigt pipe. (no cat) When i get on it hard my turbo screams. More like squeals like a pig. What's up w/ that? Stock turbo btw.
If its a screaching noise then that is normal and just the turbo, if it sounds more like a kazoo its a boost leak. If the noise wasn't there befor the exhaust then its prob ok.
I think I have the exact same thing going on with mine. I have the magnaflow cat back and once you get over a certain rpm or throttle or something it makes a lound airflow noise?
I wonder if it might be the vanes close then they open back up again? But the noise dosent seem like it goes along with what the vane position says in efilive?
my LMM did the same thing after i tore all that DPF and cat crap out of it, you can hear the turbo wine down after she builds boost, but at 1600 rpm's, she has a nice clean wistle to her, i love it