If you use a carb enclosure like Fasttoy you can pretty much use any out of the box carb. If you use the carb hat you are going to have to modify the carb to work with boost being forced into it. The throttle plate shafts have to be modified etc.. etc.. so there are no places for the pressure to escape. On a roots supercharger none of these carb mods are needed since the supercharger is after the carb. If you need a list of what has to be modified for the carb hat I can dig it up for you.