The Subaru Impreza fuel tank design is flawed particularly when running below half a tank of fuel. It’s possible to encounter fuel surge on hard cornering and spirited driving as fuel moves around the fuel tank and away from the fuel pump. Fuel surge occurs when the fuel pump sucks in air as it is no longer submerged with fuel. This results in a fuel cut which from a driving perspective is quite aggressive as power from the engine is immediately cut. With increased levels of grip and higher G forces associated with track cars, this is even more pronounced as the engine is starved of fuel.
This design problem was overcome by Subaru on the Spec C model with this redesigned fuel pump assembly.
The housing helps keep the sock submerged with fuel, maintaining a steady flow of fuel and preventing fuelling issues.
This is a direct fit to all 2001-2007 Impreza models but can be retro fitted to earlier GC8 models.