Set the balance at 140 mm. With the plane trimmed to fly hands off in level flight the plane will climb when flown inverted. This is how you have to balance them to perform. The newer kits don't need the back of the fuselage or the rudder fin beefed up as the factory has made these mods already. To torque roll you may need more engine. I put a Thunder tiger 36 pro in mine and it didn't have the vertical I needed. I put a Thunder tiger 46 pro on the plane and it is closer to having the vertical power I need. I am still experimenting with props.