Over the last couple months I have been spending al my time putting a junkyard tbi454 in my beast. I finally got her running good except with heavy throttle in 3rd or OD she sounds like a diesel at low rpms. So is this the noise a lifter would make or do I have a bad rod or something even worse? Could she just be pinging bad?

Charlo

 

Sounds like detonation to me, especially if it's in a high gear and under heavy load. Retard the timing some....