The EJ25 Subaru engine is infamous for leaning out CYL. # 3. The stock fuel rails and lines allow more fuel and pressure to be distributed to the other cylinders. When STI owners begin upgrading the engine and adding more boost and more power to this the problem gets even worse. The Perrin Fuel Rail Kit solves those problems. By redirecting fuel to both banks of cylinders as well as the regulator, even fuel distribution is guaranteed. Kit includes billet aluminum rails with stainless lines and fittings. This part is designed for use in all STI's. However, aftermarket electronics are strongly encouraged.
