Even with a ported head, you are still "over-carb'ed". Save yourself heaps of time, frustration and money, and sell the 29s and install some well tuned stock carbs.
Perhaps set the 29s aside and wait for a built up HiPo motor to use them on. Porting alone won't be sufficient to create the vacuum pressure necessary for these pampers. They're specifically designed to produce fuel flow rates necessary for high lift, high duration, higher compression motors that require more fuel in upper rev bands than your stock motor generates.
Best of luck-