but then you really are in the lap of the poetic licence, with ambient temperatures and think of your first number....its all a bit made up!
Never understood that. If its all made up, how can you have bhp limits in racing? What does it mean? How do you know if cheating or not? Sure they can change a little given temp, altitude I'd guess and a few other factors, but are the developers of these really not able to make approriate allowances witin their machinery to calculate a flat line ambient temp etc so as to have meaningful outcome?
From my understanding results can vary between dyno's and operators so as long as you use the same dyno for checking the results of any changes you should be ok.