I always ran a K&N Stubstack with the carb sealed to the scoop. On the last deal we ran, we paid attention to the shape of the pan in the scoop and used a K&N tall velocity stack style air cleaner without oil. Just trying to straighten up any turbulence and keep the big stuff out and it made a difference in how the cylinders looked after a year. Never tried A-B-A tests. Ran good MPH and seemed happy.