Brushless Truggy gearing

I'm working on a brushless truggy conversion for my hyper 7 PBS. I plan on using the dominator center slipper with a 65T plastic spur. I was calculating the ratios, and with a 12T pinion I get about 16.6:1 from the motor to the wheels. This seems too high to efficiently turn Maxx size tires. Does anyone know of any mod 1 pinions below 12T? The optimum gearing of around 24:1 would require a 8T pinion. Should I just go with a e-maxx tranny or maybe another modified twin force tranny similar to my E-savage?