if its a 20C pack that means it should be rated for 74A constant and 30C (111A) burst. I see spikes of over 120A on my 1/8 buggy on a 4350mah 5s pack. You are for sure pushing that pack. But it should be able to do it. The flightpowers are the best lipos out there right now.
I can't decide if its more fun
to make it...
or break it...