this is from a sales website:
The second generation Super AFC follows the highly successful Super AFC in an upgraded package. The Super AFC is a vehicle specific fuel computer that modifies the air flow meter signal/pressure sensor signal and allows the user to either richen or lean the fuel mixture. Adjustment ranges from +/-50%. The Super AFC boasts an 8 point adjustable fuel curve with 500 RPM increment setting points. The Super AFC also allows the user to adjust fuel enrichment according to either LO/HI throttle positions. The AFC also cures the erratic idle problems associated with open atmospheric blow off valves on hit wire air flow meter equipped vehicles. Monitor Mode shows analog meter faces, Y Graph Display, Numerical Display, Peak Hold, Replay Mode, 1 point/10 point and ghost map tracing. All correction factors are also displayed in percentages. All values and graphs are displayed through the exclusive VFD (Vacuum Florescent Display) screen