Without the thread search function it's a bit hard to say whether or not this has been answered, I just put my rc18t together with mamba 6800, I am running 15/55 right now with a 6 cell SMC pack, is this a bit high? The thing is a rocket, runtime seems good, but the motor is getting pretty hot. I was going to try 13/55 and see how things went, I found posts of other running 15, but they all seemed to be on 3 or 4s lipo.