Depends on where you are. In the east it is Joe Curto in New York,(718)762-7878
and in the west it is Rhys at Island Automotion, (250)479-5482
Either one can and will discuss your problem and help you obtain the best
solution.

If I were you I would forget "tweaking" until you get them on and running
right. They are big enough that the butterfly screws only add a little
desirable turbulence for better mixing, in my opinion. And if you take off
the split ends, you run the chance of loosening or losing them down the throat.

Things you should pay attention to: Dashpots, float valves and especially
throttle shaft seals. Of course the bottom plate seal is also important.
--
George Downs Bartlesville, Heart of the USA!