Above 45 degrees your G factor also increases: 1.41G at 45deg, 2G at 60 deg, 5.76G at 80deg. That means you also have to fly faster by the square root of the load factor to not stall. So for example if your stall speed level is 60, it's 71 at 45deg, 85 at 60g, and already 144 at 80deg.