Battery ?

I built a tarot 680. It has 6 turnigy multistar 880 kv motors, 30a simon k esc's and 12 x 4.5 CF props. All up weight w gimbal and gopro is 2.3kg. Currently running 3s batteries. My question is: should I be running 4s? I get about 12-13 mins with a 5200 3c 3s. More efficient w 4s??
 


Top