More Voltage = Less Amp Draw?

[DLS II]

Hi, one of my other project cars is a RC-10L2. I have on hand a Feigao 380c 13t(3125 KV). As a test I once put that motor and a Mamba 25 in my Yokomo YR-F2 (6 cell nimh) and it performed much like a 19t brushed. The Mamba 25 barely got warm. Do I dare put the Mamba 25 and the Feigao 13T in the RC-10L2 with a 4s lipo (20c)? I do know the instructions say that 4s lipo is " at your own risk". Am I going to smoke my Mamba 25? Thanks, Don