Looking to buy/build 500-600 fwhp 360

Well, I bought the rotating assembly so I don't know if I can get zero deck. I'm getting the compression ratio off the Hughes engine web site. I might port the heads and run a bigger roller cam. I don't plan on running nitrous very much, and it's a 4 speed so I can lower the static compression ratio a bit and put in a healthy cam to build pressure. At least I think I can do that.

Why lower the compression and use the cam that way?