Trick flow 270s or 240s on a 383?

I agree. That’s not the best comparison. But I get the thoughts behind it. There two totally different shape size length ports.

If you can fit the 240’s on the 383, even if a bore notch is required, go for it. That is going to be plenty of head for that engine.

Food for thought, small block guys can run 9’s with less head. (And cubes) OK, it is more of a race car, but not a full tilt one & as well as lighter, but the power can be made.