The carb that comes on a Homelite 30 has a 5/16" bore. The carbs that people are recommending to you have a 7/16" bore.

You have to measure the carb at its venturi position (hard to do). This is the minimum diameter of the carb's bore. The 1/2" that you are reporting to us must be the diameter of the carb at the point where it attaches to the engine?

How did you determine the correct timing position for installation of the magnet into your prop driving hub? TKG is suggesting that the relationship to trigger your ignition system be set to occur at 28-30 degrees before top dead center of the piston stroke.

Enjoy,

Jim