GRP Engineering Injector Adaptor / Spacer GRP Engineering Fuel Injector Adaptors are designed to extend short or 3/4-length fuel injectors to suit 3/4-length or full-length applications. They provide a precise and reliable solution when adapting injector height for various fuel rail configurations. We have both upper adapters to suit the common 14mm aftermarket rails and 11mm to suit more OEM style fuel rails. If you are unsure which adaptor is required for your setup, please contact our team for assistance. Features: Precision-machined for accurate fitment Suitable for E85 and other ethanol-based fuels High-quality Viton O-rings for superior sealing and durability