Nick with the servo system you do not need to have it on the cobra. It would also be a very cool thing to see put the high rpm servos on that gear ratio the z would have the same speed give or take as the x & y this is what we have on the stinger. This would put the z on a cobra at or arround 1500 ipm and although cool to see I would not do it. I can only think of a 4x8 sewing machine. But the servos will do the trick on the speed no prob. I will post a video of the x3 with the servo by Monday.