confused - or just a stupid question

The heads have been slighlty milled. The piston is at "0" deck. My engine rebuilder was talking about how 318's suffer from compression due to the piston being too far down. I used the performer not the RPM becasue I have the stock heads. If I had 360 heads then I would go with the performer RPM due to the larger ports. Besides, the intake was free. I had a 570cfm Holley Street Avenger at the first startup but had to be removed becasue was junk. Dumping way too much fuel. I bought it off ebay and thought I was getting a good deal, apparently not. Someone basically drilled larger holes in it. Its ruined. I purchased the 500cfm from a friend who had it on his 318, since he put a 340 in his car, he sold it to me in almost new condition. Next week I am taking the car to my other buddy where we will advance the timing more (Probably between 34-36 degrees) and possible re-jetting. Like I said, one day i'll have a better rear end set up.