[G.M.]

F-1-- What do the plugs look like? They will tell you by looking at each plug how the mixture is. I like to see a few dark spots on the flat surface below the bottom end of the threads. If it is lean there will be no black and will be a very light tan. To rich and they will be covered with black soot. I have adjustable main jets and can tune them by looking at the plugs or with an exhaust gas anylizer. One jet could be a differant size or have dirt in it also. The front plug on each side represents the different sides of the carb that feed them. One side of the carb don't feed one side of the engine, it chriscrosses. If I recall with a steel intake the passenger jet feeds the front plug on the passenger side. The drivers side main jet feeds the front plug on the drivers side. With an aluminum intake the passenger main jet feeds the front plug on the drivers side. I may have the alum and steel backwards but you can look at the manifold and track the fuel, air "runs". In some of the Ford service bulletins there are diagrams showing the flow through the maniflod. Try the Marvel Mystery Oil to free a sticky valve before you get into "neverland. G.M.