I am not going to give you an overview of Fords GT40P here, but rather, I am
going to direct you to the best source of GT40P information available in the world. Probably the universe too, who knows?
Ford's GT-40P Cylinder Head
The link above will get you to the new "updated" page. To get straight to the old page that has the specs and other hardcore P stuff, click Here
If what you want to know isn't there, you don't need to know it.
Enjoy! And come back now!
More good stuff!