1. How do you know the supercharger has been removed?
2. That is a regulatory limit (250 knots below 10,000 feet), not an aircraft performance limitation.
Correct. And even without the Supercharger it would still be fast as heck down low.
Gunfighter, one of two other CAF Mustangs, has its supercharger.
Some of these modified as racers are doing 500 mph on the deck.
These airplanes are maintained by volunteers, not the government. So one airplane is more than enough for a squadron these days, given the personnel involved.