When ever I "floor it " I get a backfire bang that just started happening. Any ideas what could be causing this ?

 

My experience with backfires has always been an electrical issue. Check spark plug wires - make sure they are all seated on the plugs all the way, check timing again, check plug wires at distributor, and take a volt-ohm meter to each plug wire to see if there's one with a break in it - even brand new wires often come with breaks in them.

 

Cool, thanks. I will look into those items in question.