[diets]

I have two different setting for my 4x4x4.

The above mentioned dual motor setting with approximatly 1:400. It is slow enough for crawling and has more torque the it will ever need.

The single motor setting, with one Topcad R02 modified with extra neodym magnets. The transmission consists of spur/diff gear combinations of the stock mini-x. The gear ratio is 8:35 for the center diff and another 8:35 on each axle. So i have a an overall gear ratio of 1:19. The mini-x goes pretty good with this combination. Enough torque and speed for an offroad track.

So i think your mini-z setting should be good as well. You can use larger spur gears if you like. The torque should be high enough.

diets - will show more pics of the 4x4x4 soon