If I understood you correctly, you are using 8 pcs of 10 Ohm/50Wt resistors? Probably connected in parallel, which makes the total resistance of the resistor bank 1.25 Ohm.
Voltage of a 6-cell pack at the beginning of discharge is ~7.5V, so the current would be 7.5 V/1.25 Ohm = 6 A. That's quite far from 85 amps, so something definitely does not match.