Where to look for casting numbers????

I am trying to figure out exactly what kind of heads I have on my SBC? Does anyone know where to look for the casting numbers? Also, Does anyone know if there is a website to go to, to find out the exact specs on my heads based on those casting numbers? I am trying to find out what the chamber size is on these heads so that I can calculate the exact compression ratio. Thanks in advance for all your help!

Must take off a Valve cover. Most "chevy" guys use last 3 #'s to ID. And a liltlle tip off is the more power the motor the better the head. Get the #'s and I might be able to find out for you.

Try this bud!
http://www.mortec.com/location.htm
HBjet

Yep HB has the ticket load your printer up and get ready for a book

if you are tring to find the EXACT compression ratio you must remove your heads and cc the combustion chambers then the cylinder piston volume then add in your head gasket thickness and you will be close to exact CR.The head specs. you seek will give you a general estimation at best, because in order to know exact cc you must know the piston deck height and cc for valve reliefs along with combustion chamber of your heads.good luck!