The IAG Performance Side Feed to Top Feed Fuel Rail Conversion Kit is the ideal solution for older Subaru platforms that are limited by factory side feed injector options. Many previous-generation Subarus are restricted to a small range of injector flow sizes, and converting entirely to a top feed system can be costly and complex. IAG simplifies the process by allowing you to retain your existing side feed TGV housings while converting to modern, high-flow top feed injectors.
This complete conversion system replaces the factory fuel rails with IAG’s billet aluminum top feed rails and includes injector conversion bosses, mounting hardware, spacers, and seals. With this setup, you can install your choice of top feed injectors without replacing the intake components, significantly reducing cost and installation time while dramatically improving fueling capability.
Beyond compatibility and cost savings, this kit is designed to address a major weakness of the factory Subaru fuel system. OEM fuel rails operate in a series layout, meaning fuel is delivered sequentially from one cylinder to the next. As power levels climb beyond roughly 350 whp, this design can result in uneven fuel delivery, causing the last cylinder to run lean. This imbalance increases the risk of detonation and potential engine failure.
IAG’s fuel rails eliminate this issue by using a parallel fuel delivery design. Each cylinder bank receives equal fuel pressure and flow, ensuring consistent fueling across all cylinders. The rails feature a large 5/8-inch internal bore and are machined to accept -8 O-ring boss fittings, dramatically increasing fuel volume and maintaining stable pressure at high horsepower levels. These rails have been real-world tested to support up to 850 horsepower, making them suitable for both high-performance street builds and full race applications.
Manufactured in-house at IAG Performance’s facility in Westminster, Maryland, each fuel rail is CNC-machined from a solid block of 6061 billet aluminum and finished with a durable anodized coating. The rails are laser-marked with the IAG logo for a clean, professional appearance that matches the performance-focused design.
Included:
- Two billet aluminum fuel rails
- Four side feed to top feed injector conversion bosses
- Four mounting bolts
- Four standard long phenolic spacers
- Four injector O-rings
Directly tested for compatibility with:
Injector Dynamics 1050x, 1300x, and 1700x injectors
More Fitment Info:
