You are using volume measurements but if you are measuring out the flour textbook style, I estimate that your recipe is producing a bit over 31 ounces of dough. If you are using that full amount of dough in a 16" pan with the dough out to the edges, I calculate that the thickness factor for the dough is around 0.155. That number suggests a very thick crust--one that can easily end up being underbaked in parts. Since you didn't indicate what style of pizza you are making, e.g., New York style, American style, pan style, etc., it is hard to suggest an amount of dough that you should be using with your new pan. However, using less dough in the pan would be a step in the right direction.
I also estimate that the hydration of your dough is around 68%. That number may or may not be correct because I am estimating the weights of your flour and water which you have been measuring out by volume. But if 68% is anywhere close, then the high hydration of the dough may also be contributing to the underbaked condition you mentioned.