E-maxx w/ Feigao 540C 8XL pinion selection

[GorillaMaxx360]

will the 7xl work good on 16cells with 125b controller. Aslo with nicd cells matched of course how long of runtime do you get before you start to lose voltage and how much voltage do you lose. Can this be related to a associated 18t for example on my brothers 18t he gets 20 minutes out of it it seems to get about 15 minutes with a unnoticable voltage drop in the 16 minute we start to notice the battery is dieing but not dead like 60percent of voltage is being applied to the car. after about 18 minutes the battery is about 40 percent dead. and on the 20 minute the battery is about 20 percent of votage left and it is enougt to bearly move the car slow on only flat pavement. Should i expect the same way of battery voltage loss in a maxx with roughtly any were between 37 and 4300 mah batteries. not talking about runtime just about the time i get before the car is to slow to drive does these same nicd prinicples apply to a maxx as it would the rc 18t.