Billet Performance Products injector to plenum adapter is built for Nissan RB25 and SR20 applications that need the injector to seat correctly in the plenum side of a custom fuel system. It is commonly used on R33 RB25 and S14/S15 SR20DET builds where aftermarket injectors, rails and manifolds are being mixed together. In workshop terms, it helps turn a pile of compatible parts into a fuel system that actually seals and locates the injector where it should. That makes it a practical piece for EFI refreshes, turbo upgrades and full engine builds that are moving beyond factory injector hardware. FEATURES MPN: BPP2503 Engine fitment: Nissan R33 RB25 and SR20DET S14 / S15 Injector fitment: Suits injectors with a 14mm lower O-ring Seal: Integrated O-ring for a leak-free fit Finish: Black anodised Manufacture: Made in Australia TYPICAL APPLICATIONS RB25 and SR20 custom EFI setups S14 and S15 turbo fuel system upgrades Injector and manifold conversions on tuned street or drift cars Workshop fuel rail and plenum combinations using larger injectors FITMENT NOTES Designed for Nissan RB25 and SR20DET S14 / S15 applications Requires injectors with a 14mm lower O-ring Confirm manifold bore, injector height and rail alignment before ordering Intended for custom EFI systems rather than stock side-feed injector arrangements