Well the first thing I would suggest is learning about and "venturing" into lipo batteries.
If you insist on going with the nimh batteries you have, then I would suggest getting an EVX-2 and using a pair of your current batteries with the stock motors.
opinion, low turn motors are not the way to go unless you are racing. They don't last long on the higher voltages that make them really scoot.
The stock 27t motors respond well to higher voltages, and in a clod, with it's low-gearing they will last too. I run a castle creations sidewinder-3 (SV3) in my clodbuster (the stock-ish looking one). This is a programmable brushless esc that has the capability to run brushed motors as well (once you program it). I have a pair of Y-harnesses soldered up and plugged into it. My motors are wired in parellel and direct soldered from there using heavy gauge wire.
There is nothing magical about the esc I am using... it was handy.... if I had something else... I would have used that too.
The main thing for me is.... using the stock motors... with a 3-cell lipo battery... and using high current connections... or direct solder connections.
A 3 cell lipo battery will say 11.1v, however, that is a discharged rating. A fully charged lipo cell is 4.2v, so I'm starting out with 12.6v.
FYI, the operating safe range of a lipo cell is 3.0v-4.2v, however, most of us run more like a 3.4v-4.2v window. Most programmable esc's I set it around 3.2v-3.4v for a power cut-off, and most non-programmable esc's cut off somewhere around 3.5v per cell.... so once voltages drops that low under load, the car will sputter or just plain stop, preventing you from over-discharging that battery. Most esc's these days have a lipo-safe cut off, but don't assume, always check.
I hope this helps you, and also... this is just my take on it... there are many ways to go about it.... and many opinions, this is just what I have settled on after much trial and error.