ratio is around 2/1~2.5/1,
the bx is 2.2/1 i think, uses a 84T spur 48pitch.
most of the 4wd's are rather tight on space for electronics.
your motor might not even fit if its more then 36mm.
i think it wouldnt work in my 4x4.
also, an sb v2 is a shafty.
real sweet but also shaft drive is the predator x11.
http://www.ttechracing.com/x11/