It flies best with an initial pull of 4 G. G is not constant during the loop.
It may be half a G at the top. On cooler days, I can fly the loop at 3 Gs for
the initial pull; it is easier on the 50+ year old wing. But, when not doing
low level airshow loops, 3 G loops are always OK at higher altitudes. The
problem is getting too slow at the top, which is uncomfortable during an
airshow display.
VL