Been a few years since I was last here, so quick catch-up, my original engine bit the dust when the oil pump went out, so I dropped in a "new" engine and transmission that I bought from a friend. Had it going for about a year, now there is a strange bearing noise coming from either the engine or transmission only at idle and mostly when it's warm. It sounds similar to a dry, slightly worn bearing, but it goes away once you get it above 1000 rpm, and I hear it mainly inside the vehicle, below the dash area. The transmission seems to have a hard time deciding which gear it wants to be in on hard takeoffs from a dead stop, but is fine if I start off slow and then floor it. There is also a strange whistling noise that sounds like a mini jet engine shutting down immediately after I turn the engine off (possibly Spectre cold air intake?). I never had any of these noises on my old engine and transmission, need help cause I dont want to end up on the side of the road again.

 

could be your accelerator cable laying on the pcv hose the noise will travel through the cable so you mainly hear it inside.
as for the whistle when you shut it off it probably is the cold air intake mine does the same.