Tacking on to this, @EvgeniyFurtim, in the thread he linked, there is actually a little mod that the OP made that solves the mixture problem if you have a hardware mixture lever. He’s made a version for the Turbo Arrow, Seneca V, and Rob Young’s Turbo Bonanza mod. It works fantastic and totally fixed the turbocharged experience for me. It may not work that well if you don’t have a hardware mixture axis though because automatically moves the virtual mixture levers in game.
Edit: Link to mod thread. Mixture Behavior Mod for Turbo Arrow, Seneca V, and Turbo Bonanza