Autolite Spark Users Only

[billybronco1]

My 36 runs very rich, carb has been replaced and adjusted more than once. Current plugs are Autolite 388 and by what I have read that is a pretty hot plug. Plugs are black as well as the tail pipe, no smoke. I see a lot of people use the 216 or 386. Should I stick with what I have or try something else? What do you use "Autolite users only please" not to confuse the matter.