Flow numbers and max HP potential
The Moroso chart only shows a 1MPH difference between actual(165) and theoretical(164) based on the 8.33 ET.
The car ran 1MPH faster than what is theoretically necessary to run an 8.33ET.
(So, between your calculator and mine...... we have two different projections of ET vs speed. They can’t both be right.
The car actually ran 8.33@165...... so doing that is absolutely possible).