I have seen kids your height on the 177cm. The afterbangs centered mounted ride shorter. Its all the skiers opinion. If you like longer skis, get the 177 cm, if not get the 166.
you should be fine on the 166. dont buy a new pair till you actually grow out of these. Im tired of everyone saying go bigger go bigger. Its really not necessary most of the time.
im 6 foot and i ride 155's no joke. its just what i could get my hands on for about 60 bucks so whatev. but really just get what you feel comfortable with