Trick flow 270s or 240s on a 383?

I currently race a 383 and now my third "906" head has developed a crack. I am thinking about getting a set of Trick flows. The engine is .060 over which makes it a 394 cu in. The bore is 4.31" which is smaller than the minimum bore recommended by Trick flow (4.32"). The engine has 12.5-1 Trw pistons, a Hughes .587/.602 lift 290/296 duration solid lifter cam, and an M-1 single plane intake. According to the internet a ported "906" head with bigger valves might flow in the 280 cfm range. My heads were home ported and I don't know the flow and probably flow less. I see that a 6.4L Hemi Apache head flows 339 cfm at .600" lift while the 270s flow 343 cfm at .600". So I am leaning to the 270s. I am worried the 270s might be to big and be lazy at low rpms. Anybody have any recommendations?