I need help finding a safe trade-off

[KTy]

As I desperately wrote here ,

I need to find a jetting trade off between two combos on a PHBH 28 with mazzu crank, simple Polini manifold, adjusted Polini 177, Leo pipe and ignition is set to 18°.

* Cutaway 40, main 130, slow 55, X2 needle, needle clip 2nd from top, AV262 (actually it is a CF262, discussion here) -> engine runs perfectly at low and high RPM, too lean at upper-mid RPM (I almost seized)

* Cutaway 40, main 130, slow 55, X2 needle, needle clip 1nd from top, AV264 -> engine runs perfectly at low and high RPM, too fat (4Ting) at lower-mid RPM. I tried a 50 idle jet, "4Ting" is still there around 30% of the throttle.

Is there a compromise on the needle, or the cutaway, or do I have another issue, like an air-leak, faulty carb... etc

Reading from there, my understanding is that I should try an X7 needle....

Thanks

[Manucci]

Did you try a X3 needle?

[KTy]

Nop, I will !