I don't think the Moroso Calc is RWHP. I think it is net actual flywheel hp. Of course, no one really talks actual hp numbers, it is always corrected to standard conditions. I think people get what looks like logical RWHP numbers from the Moroso Calculator, but they fail to take into account atmospheric conditions. Therefore it is more of a coincidence the hp number look like RWHP. You need to correct the mph to standard conditions before you plug the numbers into the calc.