i ran a 14lb cap on the original radiator in my charger. had no problems with doing that.
if your system is in good condition, i see no reason you would have any problems with a 16lb cap.
for a long time, 7lb caps were what everyone recommended. and every time you parked, the car seemed to puke.
my recommendation is to hide a good recovery tank somewhere, run a 16lb cap, and enjoy the benefits of a closed system while looking factory stock.
just my opinion. your mileage will vary.