Michael: You have my curiosity up, just what is "something really different about the sound of a real 427 (I presume you mean 'original 427') that arruminium block and head engines don't have?" I've always thought that 427s sounded similar, of course depending upon how high the compression is, how radical the valve timing is, how minimal the exhaust is, etc. Of course I often have my earplugs in when I hear some of these beasts...
Rich