I’ll like the Trick Flow 270 heads, I use them on a 558 RB it’s a great low revving street/strip engine.
Mine has max hp at 58-5900 rpm and max torq at 4500 rpm with a single plane and a comp solid roller (275/282 deg. and 657/659 lift).

Keep in mind that the 270 heads will raise the intake since the runners are extended, I don’t remember how much but I guess around 1/2 inch higher ...