Drills for follow through?

I video tape myself when i pitch and i notice that i follow through much better when i throw my offspeed than when i throw my fastball. When i through my offspeed, my back is completely flat but when i throw my fastball, i am probably around 60 degrees. I was just wondering if anybody could give me some drills to do to get me a flatter back when throwing my fastball. Or is this a normal occurance?

Your follow through and how you finish is largely a result of what happens earlier in your delivery so your focus should be there. Post some video and we can help.

Why do you want a flatter back?

the timmy L. pick up the dollar from the dirt after every pitch?