Hello guys....

I Built a Sig Mid-Star 40 last year and i have a big problem.
I build the plane as described in the book, with no modification at all. I adjusted both ailerons streamline with the bottom of wing before the first flight. When i took off for the first flight, the plane started to roll (i don't remember right or left) at a fast rate. I had to put the trim for ailerons fully to one side (left or right i don't remember) on remote to stop the roll. The plane has a OS 46 FX and the wing look straight. When i landed the plane, i looked at the ailerons and one side in 1/4 up and other side 1/4 inch down, and that is to make the plane fly straight !!! I know that we should put some "right thrust" on the engine and i just noticed after measuring my plane that my engine is at 0 degree, no right thrust at all. Do you guys think that it can be my problem ??
Having no right thrust would make the plane roll to the right or to the left ?? Finally, how many degrees should i put, considering that i put a bigger engine than they suggest. Should i put a little more right thrust ? If that's not the problem, what else can cause the plane to roll so fast ? ... a warped wing ?

Thanks all for your tips and help. really appreciated