[BigBlocksRule]

You ain't gonna be anywhere near 9.5:1 with flat tops and open chamber heads, period.
With 119cc chambers and 3cc valve reliefs with a decked block and .040 quench, you'll be at 8:1. It'll take a small dome to get you up to 9 or 9.5:1.
With a good bit of port work, large valves, etc., you'll be as good as entry level aluminum heads, I've seen well done ones flow in the 340cfm range. They won't hold a candle to a good race head which are all well over 400cfm, but will be great for daily driver or mild racing.
Don't get too tied up in big port work...stock valves with a good bowl blending and a bit of short turn work, good 3-angle valve job and some necked-down valves plus some small dome pistons will get you a very good head, capable of 600hp or so on a 454.
Or forget the domes, go with a forged and studded bottom end and add forced induction, that's a perfect compression ratio for a hairdryer or huffer!