You seem to be using a great LiPo battery pack. You can adjust the speed and torque slightly with pinion and spur gears but it is the RPMs of the electric motors that make them run faster. A 13.5T brushless motor is about 3000 KV motor and spins at around22,000 rpms. I am lookng at putting a 4900 Kv motor into my TC4 along with a 5000 40C 2S battery pack.
I posted to see what others are using but not got an answer back on what others use. I do not race mine but would love to hit the onroad track again that is about 40 miles away. My 2002 MugenMTX 3 has not been run in about 6 years and would love to take it out again. Need to purchase some 35 Shore Foam 30MMtires forthe rear and 28MM tires for the frontsince the old ones dry rotted from sitting too long.
http://www3.towerhobbies.com/cgi-bin...?&I=LXZMX3&P=7