You learn everytime you run it! Did you say you ran a 1" spacer on 1 intake and not the other? You can get a bunch out of the stock intake, but that being said I would KILL to take 30+lbs off the nose!
The factory cast had the "square bore to spread bore" aluminum spacer that's about 3/4 inch thick. The SD has a plastic 1 inch spacer so the gas line going into the carb don't hit an "unused" mount.