No rules dictating it.
But my belief is and he can correct me on this. Is that you want the most power and tq from 3000 to 7000 rpm.
So you size your port, valve, everything to obtain that number from a certain CID.
As Jesse previously stated we missed the cid or port size or both.
This port was pulling well passed the 7000 rpm and still making power.
We have another block that is 370 cid.
Its a 3.795 stroke 5.7. May end up swapping the short block to see the results.