Magnum replacement heads

I guess the other question is, how much power are you trying to make, out of how many cubes, and how mild/wild is the overall combo going to be?
How much flow do you think you’ll need to get there?
Customer would like to make 400 flywheel hp, with a stock short block, (360) a 214/218 @.050/ .532/.539 lift hyd roller cam. These heads and a edelbrock air gap. Not sure this can get there