Stage X V5/6 TOP FEED FUEL RAIL CONVERSION KIT

Stage X billet fuel rails suit any performance engine project. They are designed and manufactured for top-feed injectors, where improved fuel feed and routing are essential.

In Subaru's standard fuel system, a pump sends fuel from the tank to the front of the car, through the fuel filter in the engine bay and into the fuel rails. Fuel is then delivered to each cylinder one by one, starting with cylinder four. The fuel pressure regulator at the end of the rails acts like a floodgate, backing up the pressure so that each cylinder has a good supply.

A more efficient approach is to give each cylinder its own equal amount of fuel, so that no cylinder is left short. This is what a parallel fuel rail design does. In this kit, fuel leaves the fuel filter and passes through a Y-piece separator that directs it to both rails at the same time. This addresses the problem of one cylinder running lean and, thanks to the larger-diameter rails and lines, lets the system hold more fuel in reserve.

This kit is designed for modified vehicles where fuel control is essential to maintaining power and engine safety. The included performance fuel pressure regulator gives maximum fuel control with minimum flow restriction for engines up to and beyond 1500 HP. Advanced bypass technology and an enlarged port design provide accurate fuel pressure control across the range, so the fuel pump can push more, draw less current and meet fuel volume demand with no pressure creep.

A remap after installation is recommended, so that all ECU fuelling parameters are matched.

Each rail is made from T6061 aluminium extrusion with a military-grade black anodised finish, and is supplied with stainless steel -6 shouldered male fittings, ready to connect to braided fuel lines. The kit also includes all necessary mounting brackets, stainless steel hex screws and rubber O-rings for a complete installation.

These rails are intended for use with either Subaru OEM top-feed or uprated top-feed injectors.