What do the trichomes say? How are you checking them? Are they clear? Cloudy? Cloudy with a touch of amber? Cloudy w/ lots of dark amber? It is growers choice on when to harvest, depending on what kinds of effects you're looking for. I like to try and hit cloudy with a touch of amber for max potency.
Have you checked out the tab at the top of this page, When to Harvest? Goof info there if you need it.