Power NOW! When turbo exhaust backpressure increases, the stock actuator prematurely blows off the seat, softening boost in the midrange and killing torque. With twice the diaphragm area and spring pressure of the stock wastegate, Banks BigHead Wastegate Actuator keeps the valve seated longer and achieves a higher peak boost, sooner. At peak, BigHead opens the wastegate and holds its position, for precise boost control that gives you crisp acceleration and more mid-range pulling power. For trucks manufactured in 1998. Build date can be found on vehicle information tag driver door jamb. PartNumber : gbe24400 Description : Banks Power 99-99.5 Ford 7.3L Big Head Actuator Assembly Add-On Part : NA Title : BigHead Wastegate Actuator Assembly Banks Power 1999 Ford F-250 Base V8.-cc Forced Induction::Wastegate Actuators 1999 Ford F-250 Lariat V8.-cc Forced Induction::Wastegate Actuators 1999 Ford F-250 XL V8.-cc Forced Induction::Wastegate Actuators 1999 Ford F-250 XLT V8.-cc Forced Induction::Wastegate Actuators 1999 Ford F-550 Super Duty Lariat V8.-cc Forced Induction::Wastegate Actuators 1999 Ford F-550 Super Duty XL V8.-cc Forced Induction::Wastegate Actuators 1999 Ford F-550 Super Duty XLT V8.-cc Forced Induction::Wastegate Actuators