if my memory serve's me right...paralell will give you longer run times....but less voltage...(ex....(2) 6 cells 3300 gp wired in (p) will be 7.2 v ...but 6600 mah)...where as you take the same (2) 6 cells 3300 Gp wired in (s) it will be 14.4 v but 3300 mah.......the 1st one will give you less Volts...but longer run times.....the secont will give you more Volts...but shorter run times......did I explain it good enough.....also if you were able to see the pics i sent you...I made my own chassis.......if not here is the thread link to pics of my emaxx on the forums here.....
http://www.rc-monster.com/forum/showthread.php?t=2736