Bought some Edelbrock Heads, Need Advice

[Jeff Chambers]

The free-drop method isn't necessarily accurate, especially if the cam is advanced or retarded.

Use the clay method but you have to make sure that you use a solid roller to do it. I've taken a pair of hydraulics, disassembled them, flipped the internals and re-assembled. This makes them solid and perfect for checking cam/head installations. Remember to only take the slop out of the rockers when you use this method.