https://youtu.be/VGdERLDnusw

It's been 2 years cannot figure it out.

It started when we removed the manifolds and installed headers. (Used hedman shorties and Y pipe).

Removed the belt still does it. Changed the gaskets on headers and y pipe still did it. Did a smoke test couldn't see anything. Disconnected one plug wire at a time still there. Pulled driver side valve cover nothing out of the ordinary.

Just bought new Hooker shorties and a dougs Y pipe with Remflex gaskets -- still does it. We are starting to think it might be trans related. My buddy FORCED me to pour a bottle of Lucas trans treatment, obviously did nothing.

In the beginning it used to be under load and barely noticeable in park/neutral. Now it's getting louder with no load on the motor. I'll etransfer $50 to someone whoever figures it out haha!

 

Torque converter bolts all nice and tight?

 

One of the next things I'd like to check. Engine and trans have never been apart but who knows.