Hughes is claiming 447 on their "Prepped Edelbrocks." I've been busy at work, but will be calling them to see how the Eddy heads compare the Indy's that they've had on the same flow bench.

http://www.hughesengines.com/TechArticles/1headflowchartscomparisons.php#EdHemi

A pic I created comparing Stage V and Hughes-Edelbrock: