Standard armature and Hi-Torque

[Hydros]

Shown below is a regular motor armature and an old Fenner/Stone Hi-toque motor armature.

They cost a few dollars more but not all that much. This babies will knock your socks off when using four or less batteries. Figure what ever you are hopping at now, add another 3rd to it.

You can get these today with the spline shafts.

[herrakani]

So the standard armature model is from the normal "street" pump?
 

[Hydros]

Yes, the hi-torque is too powerful for more than 48 volts, at least from what  I've learned first hand.  

Those hi-torques kick ass at low voltage.