ok i decided to drop the idea of vortec's the overall cost with machining will be more than a new set of heads from jegs or summit. so..
i am looking at pro lighting 23º 200cc heads or Dart iron eagle 200CC heads.. which one would be better and would 180CC or 200CC yeild more power.
here is my current set up
350 +.30 355.
cam: 280º seat to seat .512 lift
rpm air gap intake
750 holly.
th-350 with 3000stall.
and 3.73 rear gears.

compression ratio?

with 64cc heads it will be 9:5:1

You must be using dished pistons. Flat tops, with a 64cc chamber, will be in the 10.2 to 10.3 range given a .040" quench. A 280 cam will work great with 10.2-10.3. The 200cc ports will rpm a bit higher, the 180s will make a bit more torque. Given your gears, I'd favor 200cc ports.

ok thnx do the dart out flow the pro topline heads for mid range lift?