The Radium Engineering Mazda 13B-Rew Secondary Top Feed Conversion Fuel Rail is designed so it replaces or upgrades the factory fuel rail with a high-flow rail designed for performance injectors and AN/ORB plumbing. The larger, purpose-built fuel path is useful on modified engines where injector choice, fuel volume, and serviceable external plumbing matter more than the stock rail layout.

For Mazda 13B-Rew Secondary Top Feed Conversion, it is intended to integrate with the vehicle-specific layout rather than serve as a universal substitute. Injector height, upper/lower O-ring diameter, and plumbing requirements vary by engine. Match the exact application and injector configuration.