I just read all 9 pages.
I love seeing people swapping engines between vehicles - I3's or v12s lol or anything in between.
If it would be ok to put in my .02, I'd encourage you to look into turbocharging. Most engines can handle up to 5lbs of boost with no other modifications. 5 lbs isn't a lot, but sometimes you only need a little. If there is a small shop where they work on turbos close to you, maybe they would point you in the right direction.