Anyone Got A Combo Like This

Yeah, I've heard that the as cast Performer Edelbrocks wont support life to a 500ci engine. I remember seeing a flow chart on as cast performer RPM's & they were rated all the way up to 318 cfm @.700 lift. I think it was Hughes Engine.
I fugure w/ my cam they will flow around 300 cfm. I wish I could afford to have someone do some porting on them right now but at the moment that will have to wait.