I'm guessing you're running 14.8V? If so, that is a manic set-up for a track-buggy. The 2200 will be far more controllable. Or, Castle have just released a 1512 1800kV motor - which would be perfect in a buggy on 4S, where you're trying to get more control.
Yes, it is a 1/10th ESC, but it is capable of 6S, and ~80A, like the Mamba Max (which most used with a BEC before the MMM came out). I have added 3 105°C 330uF 35V caps as well, and removed the strain of running the BEC (running an external one).
Most important thing in extending your run time is to drive smoothly. Use barely any throttle coming out of corners, and slowly build up to full throttle if needed. You'll still be faster than the nitros, but you'll get far longer run-times.
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