My newborn son isn't gaining much weight. he eats 2-4oz every 2-3 hrs. he is currently 8lbs9oz at 8 weeks old. he was born 7lb4oz. anything i can do?

I disagree: I don't agree that he is not gaining enough weight. You have to remember he likely lost weight in the first week after he was born - usually about 8 ounces. That being said, the baby has gained nearly 2 pounds in the past 7 weeks. That's more than adequate weight gain, and I wouldn't make any changes in what you are doing. Continue to make sure you attend all routine baby check-ups.