4 dot -10*
3 dot -5*
2 dot 0*
1 dot +5*
0 dot +10 degrees

The X12 in mod should usually be run with 4 dot and maybe 3 dot but usually dont see 2 dot as it just raises temps and you dont see a benefit from the extra RPM's.
From what i recall the X12's had higher standard timing than some other manufacturers hence the -10* setting, I think it is like 35* timed out and most others start at 25-30* at least i think thats right

I say start with 4 dot and see how you like it

And like Brian mentioned above going to 14 ga from the normal lrp 12 ga will reduce power a bit with the increased resistance so if you liked the speed you had before you need to add a turn if you felt it was too fast for you before going to 14ga may get you the feel you were looking for