What would sound like a lifter tapping?
 

I realize that these cars dont have lifters, so it must be something else. However, it sounds exactly like the lifter tapping in my old Buick. What might be causing it?

Thanks,
Mike

There are "hydraulic elements" in the ball studs, which push up and hold the rocker against the cam. If they get weak, they don't hold it tight enough and you get a click.

It could also be a worn rocker arm or cam lobe. Best attend to it while it is still possibly a cheap repair.

To expand on what Chuck said, I had a tap on the 560. Turned out to be worn cams, one lobe on each cam. The result at that point meant new cams, new cam followers and new ball studs. Most likely at the onset it was just weak hydraulic compensators (ball studs) which created too much gap between the follower and cam lobe, which in turn ate the lobe. That works out to a pair of cams ($$$) and 16 followers and 16 ball studs ($$$$$$$).