The IAG V3 Top Feed Fuel Rails are designed to increase the power ceiling on your Subaru’s fuel system. These fuel rails replace the OEM rails on 2002-2014 Subaru WRX, 2007-2021 STI, 2008-2012 LGT, and 2006-2013 FXT. Machined from high-quality billet aluminum, these rails offer an exact fit to the IAG PTFE Fuel Line Kits. If you're upgrading your fuel system, IAG's V3 Top Feed Fuel Rails ensure consistent fuel flow and enhanced performance, making them a perfect match for high-performance applications.

The IAG V3 Top Feed Rails are precision machined from solid 6061 billet aluminum and feature an anodized black finish with the IAG logo engraved on top. Chosen for its durability, lightweight properties, and corrosion resistance, 6061 billet aluminum ensures that these fuel rails can handle the extreme demands of high-flowing, high-performance fuel systems.

Subaru’s OEM fuel rails function in a series, which means that each cylinder's fuel is delivered after the other. As horsepower rises past the 350whp mark, the stock rail often does not have the capacity to deliver fuel to the last cylinder effectively*. As a result, that last cylinder can run lean, which can result in catastrophic failure. IAG billet fuel rails are designed to eliminate this problem. First, our fuel rails operate in parallel format, each cylinder bank receives equal fuel, matching the flow between the rails ensures that each injector sees the same fuel pressure. Second, the bore of our rail is machined to 5/8" ID and is designed to accept -8 O-ring boss fittings. This configuration greatly increases the volume of the rail which means that more fuel is available at higher power levels and IAG's fuel rails were real-world tested to 1000hp.

IAG’s V3 fuel rails incorporate the use of phenolic spacers located between the rails and the TGVs. These phenolic spacers play a crucial role in reducing heat transfer from the engine to the fuel, maintaining a cooler fuel temperature as it enters the engine.

The IAG V3 fuel rails also feature a port to add an optional fuel pressure pulsation damper between each pair of injectors. Fuel dampers absorb fuel oscillations caused by injectors opening and closing. All Subaru's are equipped with a fuel damper however its location is some distance from the injectors. The IAG V3 rails locate the damper between the injectors to help maintain constant pressure.