The Edelbrock carbs will get "eaten up" by the ethanol content in pump gas if they are allowed to sit for a long period of time. If you pull the tops off of the carbs you'll most likely find some white slime in the bowls. That slime gets into the fuel passages and blocks things up. My guess is that you're actually running lean not rich due to a blocked passage. People think the stinky idle is rich but typically it is dead lean and misfiring.