Reducing RPM/Torque

I'm using the default Dash8(different panel,specs)but don't know how to make the thing respond to no throttle. I mean,if I want 10% torque to taxi I want 10%,not 25 or 30. Is there anything in the airfile or aircraft file that can be changed to give me a throttle response down to zero and stay there when I tell it to?
Thanks all
Thanks all
