The GAMI folks recommend trying carb heat to improve mixture distribution
and atomization (think flathead Ford V8 heat riser).  The Ellison Throttle
Body booth at OSH some years ago had a video of the improved atomization of
their product compared to a carburetor.  The carb looked like a clogged lawn
sprinkler with droplet size and pattern changing all over the place as the
throttle was closed.  Heat might be worth a try.  Steve Colwell