Ive built 5 very similiar 3d profile airplanes all using hand drawn TLAR airfoils, by the time i have gotten these models balanced like i like them, the CG is between 35 and 38% MAC. The latest profile i built is very similiar to the first 5 except i drastically changed the wing. This airfoil is alot thicker and i moved the thicker part of the wing toward the leading edge i also increased the wing area from 540 to 792 sqin's. I balanced at 35% for the first flight....was a very big handful when it left the ground was worried for a few secs whether i would have the opportunity to ever fly it again, But managed to land it. I, know have the model balanced at about 27% MAC, and it flies just fine. ( i balance my models so that when i roll invrted it will still fly hands off)

My question is what has drastically changed my balance point? Is it the airfoil? Is it that the tail might be to small for the much bigger wing area? If it is realated to the tail could the ralation ship of stab size compared to elevator size have anything to do with it?

Thanks, any help appreciated