Speeding ticket in PA first offense?

I was given a citation by a PA state trooper for going supposedly 81 in a 55mph zone. He claims he gets multiple readings with his radar and no other vehicle was going even 80mph. I in fact was going with traffic and I sped up to switch lanes as the car behind me kept flashing his lights at me. I was the only fool who apparently didn't see the trooper. I have a compact 4cyl car and this car I was driving was my girlfriends which is a full size 6cyl and I hardly drive it. What are my chances of beating this??