are you holding a little up elevater to get the plane off the nose wheel and on the mains as you apply throttle?you want just a bit of up elevater not enough to make the plane take off prematurely but just enough to get the nose wheel up off the ground so that you are using the rudder to ster.how much rudder travel to you have?this is the oposite of a tail dragger but the end result is the same,on a tail dragger you give a tad of down to get the tail up and off the tail wheel and use rudder for corrections.try a 11-6 prop as suggested above.