your running the same combo I am. It's been trouble free. I set my fuel # to 42 at first, then backed it off to 41. This is with a 40 shot. I don't know if that is perfect with the N20 on.. it might be a little rich/ but safe. And it's enough to go where I need to, on the occasion that 180hp won't cut it. I step up w/more race fuel when I use more nitrous. maybe 60-70% 110, again just to be safe. Good luck!