Okay, you're male, and you're 6'3", and you only weigh 163 pounds? Glad you want to put on muscle, but why were you on Atkins? 200 pounds isn't a lot for a 6'3" man.

??

Now, how about you post up how you're training and eating now (in detail - start a gym log or a journal), including your calorie and macronutrient breakdown (grams fat, protein, carb).
If you're not sure, go to www.fitday.com and work it out.

And how old are you? (Training can be a bit different, depending on your age)