This is a very good primer on the basics of protein intake for CrossFitting athletes:

A general rule of thumb regarding protein consumption is to eat 1 gram per lb. of bodyweight you carry. For people with bigger frames lean body mass is also an option, so it’s slightly less than overall body weight. An individual in need of more repair, or someone looking for increased muscle mass may want to add extra protein.

http://eattoperform.com/2012/01/30/protein-is-simple-do-not-make-it-difficult/