Can anyone tell me the purpose of this part?

[440 Charger]

Its in my 73 charger located in the driveshaft tunnel under where the front of the back seat would be. About 20 lbs cast iron

 

[JimCoronette]

I think it's for sound attenuation. Uncle Tony chucked it on his BottleRocket project.

 

[440 Charger]

I was thinking not to put it back figured it was some sound or vibration dampener.

 

[Badvert65]

I removed that thing from a big block Road Runner I had and never noticed a difference.