Air fuel mixture route on any Siamese port Stovebolt head: air comes in the side of the typical oil bath air cleaner and turns NINETY degrees to go down to oil surface, turns ONE HUNDRED EIGHTY degrees to rise to level of carb throat, NINETY degrees to position over carb, NINETY degrees to travel down through carb, NINETY degrees to enter runners, and finally NINETY degrees to enter intake port.
You missed the last (and possibly the worst) of the turns. After the incoming charge hits the back wall of the intake port and becomes disrupted it needs to negotiate another turn down towards the valve. This last turn is usually referred to as the short side turn as the radius is only 1/8" at that corner.
