I 'only' am using the 2.25" and think it would make over 1000 with a couple of tweaks but, yes the 2.30' would show MINOR improvement. I'm using the TR 2x4 but, I feel if it's on a RB block and the 3x single is used it'd make more power. A custom intake 'done right' would be above that. I'm not sure at what point the head gets critically thin where it'll crack. My heads aren't done to that level FWIW.