ORIGINAL: stranger
the 27 turn was brand new tamiya gold spec the 12 turn is old the esc is good for up to 30 amps (home made) and the batteries are nimhi 3400mah high output so there is no limitation from these components on the amps getting to the motor.
How many of us run home made e.s.c's and 3400mah 'high output' cells? That's doesn't say much either, you could've been overgeared with the stock motor and harming it's potential performance...