Take a screen stainless steal or brass and cut it to fit just under your carb with holes for the bolts on the intake. make sure it´s flat or you could get a air leak when you tighten the carb back. Use a medium mesh, too fine a mesh and you will cut off air flow. What this does is break the fuel down better. Not extream horsepower gain but alittel. Also has anyone ever put an electric fan on the 1900, and if so what kind of horsepower gains did you get. Does it keep it cool, and do you have to go to a different alternator.