with the engine idling in gear ,have someone hold the brake , loosen the screws over the metering rods & swing the cover over , if the rids are up you need lighter springs under the rods , this acts like a power valve & cause a rich condition if they do not stay down , Do you know what vacuum you have aty idle ? It is very hard to set an Eddy carb to compensate for low vacuum , often the idle bleeds need to be restricted which is very difficult to do on an Eddy . are the mixtue screws sensitive or can you turn them a lot before the engine feels the change ?