Wow, I knew the P-51H was a "hot" plane, but here are excerpts from the manual thats in the public area of that website.
Specs of the P-51H-5-NA:
One Packard Merlin V-1650-9 twelve-cylinder Vee liquid cooled engine rated at 1380 hp for takeoff and a a war emergency power of 2218 hp at 10,200 feet and 1900 hp at 20,000 feet with water injection.
Performance: Maximum speed was 444 mph at 5000 feet, 463 mph at 15,000 feet, and 487 mph at 25,000 feet.
Range in clean condition was 755 miles at 359 mph at 10,000 feet, 1975 miles at 239 mph at 10,000 feet. Range with two 62.5 Imp. gall. drop tanks was 1150 miles at 339 mph at 10,000 feet and 1530 miles at 243 mph at 10,000 feet.
An altitude of 5000 feet could be reached in 1.5 minutes, 15,000 feet in 5 minutes.
Service ceiling was 41,600 feet. Weights: 6585 pounds empty, 9500 pounds normal loaded, and 11,500 pounds maximum. Dimensions: Wing span was 37 feet 0 inches, length was 33 feet 4 inches, height was 8 feet 10 inches, and wing area was 235 square feet.