Yesterday a p51 catched me in a circleclimb, and i took occasion to repeat my offline- climb tests.
I did both measurements with a 50% fuel (no external fueltank), no wep, mk108, no gondolas, climbspeed 140 (autotrimm speed)
Here are the results, time for 3000ft climb in seconds
109old 109new ratio P51
3000 45 52 0.86 54
6000 44 54 0.81 56
9000 45 55 0.82 56
12000 47 56 0.84 56
15000 47 58 0.81 64
18000 49 58 0.84 71
21000 49 61 0.80 74
24000 54 67 0.80 76
109 perfoms between 15-20% weaker now in the climb. That means about 15% less power.
I repeated also the measurement for the p51 to be sure that it is not the P51 that performs better now, but the results are the same.