Uh, where does it say the P-40 out turned the Spitfire?
Maybe my reading comprehension has gone to pot as I get older but my take on the 4 combats listed in that report is that essentially the P-40 managed a draw on two of them and got the hell out of Dodge on two of them. This hardly proof the P-40 was superior. It may be proof the P-40 wasn't as bad as some people think.
It doesn't matter how many times this report is posted or how big you make the letters.
combat 1 the fight was practically a stalemate and after both planes descended 9,000ft in 5-7 minutes the KittyHawk pilot dives away breaking contact.
combat 2. after two minutes in which the Spitfire cannot be shaken by the P-40 the P-40 breaks contact by diving away.
combat 3. Kittyhawk starts with height advantage. (how much?) and after 14 minutes the fight had descended by 7,000ft, neither plane could gain the advantage, in other words a stalemate or draw.
Combat 4, Spit starts with the height advantage. in 11 minutes the fight descends 9,000ft, neither plane can really get an advantage, P-40 uses superior speed to break away.
and we are to conclude that the P-40 was the better plane?
I have no idea why the RAAF was limiting the engines to 9lbs of boost at this time. I do know the Merlin 46 made around 70-90 less hp at any altitude up to over 20,000ft than a Merlin 45 which sure didn't help the RAAF Spitfire Vs. compared to the "book" tests in England of Spitfire Vs using Merlin 45s. Merlin 46 did make rated power several thsousnad feet higher than the Merlin 45 so a combat started at 22,000-24,000 would have gone the Spitfires way.
FTH for the Kittyhawk was around 12,000ft and in level flight it was 14,000ft or better. the Merlin 46 had an FTH of 22,000ft and in level flight was even higher.
At 13,000ft the Merlin 46 gave about 1020hp at 9lbs boost if I am reading the chart right.