P-63A-8 performance from America's Hundred Thousand, page 407-409, and graph 52.
Climb: 2.00 minutes from sea level to 10,000 feet in combat power, wet.
4.80 minutes from sea level to 20,000 feet in combat power, wet.
(Leaves the Bf 109K-4 well behind)
Speed: 378 mph at sea level in combat power, wet (faster than Dora and close to La-7)
421 mph at 17,200 feet, combat power, wet (faster than La-7 and Yak-9U)
Roll rate: 109 degrees/second @ 270 mph (thats Spit16 territory)
Max HP: 1,820 hp @ 75 in/Hg at sea level, combat power,wet.
Acceleration: At sea level, calculated to be better than F4U-4.
Calculated turning performance, no flaps: Expected to be superior to F6F-5, but slightly inferior to FM-2.
In short folks, this baby would be the best low-level fighter in the game, bar none.
Because it offered only average performance at medium to high altitudes, the USAAF did not buy many or deploy those they did buy to combat zones. On the other hand, the Soviets tested the P-63 against the Luftwaffe and found it superlative. There were some issues with a rather weak fuselage near the tail. This was corrected with the P-63A-7 (150 built). The P-63A-8 (200 built) introduced water injection, with the M10 cannon coming into service with the P-63A-9. The largest batch of A models was the P-63A-10, of which 730 were produced. P-63C-1 through -5 constituted the largest block of aircraft (1227 built). Performance was slightly better than the P-63A-8 thru -10.
The Soviets appear to have stockpiled the P-63s in anticipation of declaring war on Japan after Germany was defeated.
My regards,
Widewing