Ok, still learning,, I thought the motor load determined the amperage not the battery. The motor prop is the same I used with a 9.6 nimh 700 pack. It did not over current on the nimh and worked well. Lost the nimh pack in katrina. The voltage on the lipoly is right at 12 v full charge. The sbc is rated for 12 v. max so the lipoly is right at the max for the sbc.

If I use only 2 lipoly cells the voltage won't be but approx 7 and won't turn the speed 400 motor well enough. So I am still puzzled what to do? I don't have a 9.6 nimh or nicad to try except for what's in the transmitter.

I looked at the new jetti sbc's rated the same as mine and the new ones have a lipoly setting. Mine does not appear to have this voltage range setable.