Very many years ago I did subject work related to "g" tolerance (without trousers) in the human centrifuge at the then IAM at RAF Farnborough, incidentally home of the first RAF officers' mess.
My ego was somewhat dented when I found myself at first greying out (progressive loss of colour and peripheral vision) followed by blacking out (fully conscious initially but no vision) at about 3.1 to 3.5 "g".
The aviation doctors explained to me that they would have been concerned had I demonstrated a higher "g" threshold .
This higher "g"threshold could be expected from an older pilot who was developing arterial hardening ( thus no expansion of the blood vessels volume taking blood away from the brain) as a part of an an age related process.