Gearing Question
 

I just got a Feiago 8L and a 9918 controller for my e-maxx and was wondering what pinion to use with a 66 spur. And can I use 14 cells with this motor?

Do you have stock diffs or 1/8 diffs? For stock diffs, I would start at around a 14 or 15 pinion for 12 cell operation. I have used 14 cells with the 8L before, although it is technically not a good idea (motor will exceed its rated rpm limit). I didn't have any trouble when I ran 14 cells, aside from the increased difficulty in harnessing the power on a race track!