700 Hp on NA pump gas

Not doable with the parameters you've listed: naturally aspirated & pump fuel. It is possible with boost or race fuel with available heads.
I kind of feel the same way. It d work with boost. But if he feels like having a go at it... far be it from me to stop anyone from trying.

I guess from a certain point of view, if you look at AndyF's 470 B engine, he did make 700 HP. The small block lacks in some areas of the big block. Perhaps, just perhaps.... oh heck! I just don't know... could it be possible?

What heads did AndyF have in top and what did they flow?
Can all the numbers add up?