Strange whistling noise - Need advice.

[96BluezGT]

First time post for me.

I recently had the intake manifold on my 96 GT replaced after it blew at the drag strip and I swear the car is making a new noise since then. The best I can describe it is it's like a high pitched whistle. It doesn't happen all the time - mostly around 2200 rpms and only in 3rd or 4th gear.

I'm 99% sure it wasn't there before the intake replacement.

Any ideas as to what it might be?

Thanks in advance.