IAG V3 Top Feed Fuel Rail Kit 2007 STI

The IAG billet fuel rails are designed to eliminate this problem. First, IAG 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 the IAG 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. 

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. 

Finally, the IAG V3 fuel rails add phenolic spacers that are located between the rails and the TGV’s. The phenolic spacers aid in reducing heat transferring from the engine to the fuel entering the engine. The included spacers come in two sizes to accommodate the fitment of various fuel injectors. 

All IAG fuel rails are engineered and manufactured at the IAG facility in Westminster, Maryland. The rails are machined from a solid 6061 billet aluminum and feature an anodized black finish with the IAG logo engraved on the top.