I've just begun digging into a 1953 Cavalier with the original flathead 327 in it. I've got the air filter off of it, and I'm checking things off, but a clattering sound has started. I really don't have any experience with the straight-8, so I thought I'd post what it sounds like to see if anybody has a diagnostic opinion.

I'm guessing maybe a loose lifter, but who knows..

here it is:
http://www.twigzy.com/Voice_001.mp3