Thats about the limit for stock heads in a full body car. Of course theres weight, but thats not the discussion right now. Power out put of the iron head is.
You could get into the 10's with an iron head. It's just starts becoming a deadicated race car at that point and weight reductions and all the nice things for the street start to go away. 10 is screeeeeaming fast for stock iron heads in a full bodied car. You would have to cam heavy duty and other things that probably are not going to be pump gas/street freindly.