Whistle? Non turbo

[Chuckanut]

Hey guys, we just replace the injectors in my non-turbo 6.2 86 m1026 and when I accelerate hard there’s this whistle even when I let off the throttle until I slow down, almost like a turbo whistle, it’s pretty loud. it’s not the fan belts they’re all tight and none of the injectors are leaking. I heard that The intake naturally has a whistle, is that true? If not any ideas what could be causing it?
thanks guys.

 

[LT67]

The intake is loud, but not a whistling noise..