If we are talking about f-15E i’ll post you the flight envelope we have tried to square.
You have to bear in mind that for altitudes above 37000ft we have used the STD - 10, which means that at sea level the temperature is about 5º. Which would mean, that even carrying more GW than 40,000, you could exceed the curve of a normal STD. But I don’t know to what extent the game simulates it correctly.
I don’t have the one for the f-14B at hand, but here you have the one for the F-14A (ref 4):
I have put the red bow to square the maximum theoretical speed of 2.28+ mach. In the F-14B would be similar but with a theoretical maximum of 2.38+