just want something to go fast enough for dynamic submersion until I upgrade to static. I worked out the contartment for the control gear so there is plenty of working space for upgrading.

just debating whether to have the motors in the middle compartment and have long drive shafts (500mm)or have a separate sealed compartment for the motorspositioned to be true to the original layout.

I've been told that size 400 motors operate at bout 30,000 rpm. do I connect them straight to the propeller, or do I need to 'gear it down? I've hear a 3:1 gearbox mentioned at some point.

I was just going to parrallel up the motors off the speed controller, I was wondering if any slight difference in motor speed caused the sub to skew off to one side?