Recomened setup! Hurry!

Ill be running 14 cells so 16.8 but more like 19 volts off the charger. Um would it be better to do a revo? Can the stock diffs on that handle the power? Should I start another thread that says "what do I need to run a NEU 1Y?" Also how do you know how mush your tires are going to expand? Is this motor better then a Bigmaxximum? Cause I saw how cool the 40 mashers look when they expand! :) :) :)