I looked at using different cells, those gp2200's in particular but I couldnt find any data on discharge rates, did you? it would have to sustain 100amps in a burst (im guessing here) and 20-30 for a time. Maybe I should get some and experiment. That would be the easiest option to run more voltage but with the same weight, this opens up a lot more options, but I would have to use a different controller.
The Plettenberg is 91 or 92% efficient, i cant remember, and that comes back after a run very hot, I dread to think what would hppen to a little motor in my truck! I guess I drive it harder than I thought.
As for what I did to the chassis to get the centre section (its not a diff, just a slipper) to fit was pretty much nothing, I didnt want to start hacking the chassis up in case I didnt like it. I have now filed the sides a bit to allow the use of a larger spur gear, but the rest of it was done with plates I made. The centre section is a "slipper unit for ofna dominator" thay have them at tower, i got mine of ebay. I will be changing the design soon as I have spotted a way to do it using less metal (less weight). Here is a pic or two of how it is now:
Jay: loving the airtronics, seems just about right to me, the hitec is tempting, good for crawling i've no doubt.