How many servings of protein shake should I drink if i'm trying to gain muscle?

I'm a lineman for my high school football team, I've been drinking 40 grams (1.5 gles) or 8 ball whey 100 after my workout. I weigh 235 and eat 3 large meals and a snack a day. I workout 4 days a week for an hour and a half, I don't know if I am drinking too much or too little, how much should I drink a day?