Why is bf110 with 25% fuel max speed of 300km/h

[Blackdog_kt]

I can easily get it to 380km/h on a full fuel load with CEM enabled and that's not even with full throttle.

First of all, center the ball by trimming the rudder. Then advance throttles and RPM to the red "d" marking on the instruments, which is the maximum continuous setting. Trim out the climb, set oil rads about half-way open and water rads about 80% open and let it accelerate, trimming for level as it keeps picking up speed and wants to climb.

When you see you are not accelerating any more, drop the RPM a little bit. At around 2100-2200 RPM and 1.2 Ata i can easily get 380-390km/h in level flight.