Too tight. Remember, all flights connecting in the US need not only go through immigration (that's an easy 2hrs alone in most cases), but you also need to pick up and re-check your luggage, do security all over, TSA, etc. In Miami (which is as !!!!ty to connect at as is JFK), I almost lost the connection even with 4hrs in between. Never, ever connect in the US if you can avoid it. Connect somewhere else and go direct instead.