Guys, I read this whole post and I kept thinking BASICS get back to basics, got to be a timing/firing order problem, I been doing it for a while and even I after all I've done and seen still little basic problems still get me now and then.
you have fire so no worries there, you have fuel no worries there. I'd bet firing order and timing, I once had the left side of a v8 wired incorrectly wires crossed it ran but no power and the cat got real hot, got home and rechecked everything found out after all my double checking that I still had wires crossed got the bbok out checked it against the book and low and behold numbers 101 Matty screwup! fixed the wires and the thingran like a raped ape after that.
Moral of the story; always, always check the basics it'll get ya every time1