Edelbrock said they made that much power with that combo, no way in hell!
You want a N/A no matter what, right? Pump gas, what octane? Increase that compression to 10.5 to one at a min, you have aluminum heads, you can get a way with it. I have a friend running 11.2 on pump gas, with almost the exact same engine combo that you have, except his cam is only 220/220 500/500 112 lobe sep. He is pushing around 350 to wheels, but he has a top loader.
There is only 3 ways to really increase power, bigger cam, which for the street I would not go any bigger than 230/237 550/550 112, I do not like the higher lifts because of the stress it puts on the top end. More compression, which you can adjust with timing to a point, or more volume.
400rwhp is a tall order, what are you willing to do to get it? 350 to wheels is a lot of power, you could alway throw a little N2O to get you there
