ORIGINAL: Scratchie
I know hifgher voltage will yield higher torque, but are there negative ramifications of higher voltage?
Higher voltage pushes more amps out of the battery per unit of time.
Those additional amps make the servos stronger.
Same battery will last less time in this proportion: 4.8 / 6.0
For same total flight time the capacity (mA-h) of the battery needs to be upgraded in this proportion: 6.0 / 4.8
http://www.radicalrc.com/4or5cellsfaq.htm
Just calculate the torque you need with this on-line calculator:
http://www.geistware.com/rcmodeling/calculators.htm