OK, I was looking on
http://www.maxamps.com/ . Could I use 2 Lipoly 4200mah 5S2P 18.5V Pack and run them parrallel. Then I would be at 18.5v and 8400mah. Is that to much power and to long of run time for the 9L and 9918? I have 2 fans on the motor and 1 fan on the controler. 8400mah would give me the long run time I am looking for. Would I be ablel to get these batt. to fit on the carbon fiber chassis? They are 35mm X 196mm X 42mm .