OK, if nobody else is going to step in here...
I can't let this one go by. Maybe you meant "4%" torque, not "40%" torque.
If you meant "40%" torque, and it takes you 70% to hover (not unusual)...then, you're saying you have "fluctuations" up to 110% !! That's an overtorque!
"+/- 4%" is a "fluctuation." But +/- 40% torque without moving the collective ain't a "fluctuation" (regardless of wind change effects!) and it sure ain't normal.
Can't believe no one either caught this or cared to respond. If this is in fact what you are seeing on this aircraft, DON'T FLY IT ANY MORE UNTIL YOU BRING THE PROBLEM TO THE ATTENTION OF A QUALIFIED MECHANIC.
Yes, I am shouting.
Have a nice day.