Probably the most popular upgrade is an aftermarket fuel plate. Often the AFC (aneroid fuel control) is modified at the same time. Figure 6 shows the access plug to the AFC star wheel. Loosening the tension on the star wheel allows for increased fueling earlier in the powerband. Aftermarket springs are also available to better meter the amount of low-end fuel as desired without causing coil bind. With the AFC housing removed in Figure 7 note the location of the fuel plate. There are many choices in aftermarket fuel plates, the main goal being to limit the max allowed level of fueling. Different plate profiles control midrange and upper level de-fueling to suit different applications.