balancing.. shaft?

I know the crank pulley on these cars have a weight on them, like older GM motors have harmonic balancers. I got a pull-off from a yard but I haven't put it on yet cos it's a lot of work, and I want to make sure it's worthwhile heh.

 

wtf is this??

lol, I've never heard of such a thing.. balance shaft?

my v8s don't have such a thing.

doesn't look pleasant, or easy to get to.

 

noises:

98 camaro v6 engine noise - YouTube