The 4.0TT's high-pressure fuel pumps supply high-pressure fuel (exceeding 2900psi each) to the direct-injeciton fuel system injectors. When running turbo upgrades, especially with ethanol fuel blends, the stock HPFPs internal volumes become a limiting factor when increasing power. IE's HPFP internals install into your factory pump housings and increase the bore and piston size of the pump internals, allowing more flow, delivering more fuel, and allowing for more horsepower & torque from your hardware and tuning upgrades.
FLOW TESTING
Flow testing was performed to measure the increase in flow rate which produced a maximum result of 38.58% gain over stock!