Radium Top Feed Conversion Primary Fuel Rail - Mazda RX-7 FD3S / Cosmo (13B-RE / 13B-REW)
Suits:
- 1992-2002 Mazda RX-7 FD3S — 13B-REW
- 1990-1995 Mazda / Eunos Cosmo — 13B-RE
The Radium Engineering High Flow Primary Fuel Rail is a top feed conversion rail for the 13B-RE and 13B-REW rotary engine. Manufactured from aluminium with a large internal bore, the rail supports all necessary engine power requirements and is anodised black for compatibility with all popular fuel types including E85.
Three 8AN ORB ports are provided — the extra centre port accommodates additional fuel system accessories such as the OEM fuel temperature sensor (using adapter 14-0421), a pressure transducer, or a Radium fuel pulse damper. Phenolic insulating spacers and washers are included with stainless steel hardware to prevent thermal energy from conducting heat into the fuel.
The included 14mm lower injector seats are designed to be compatible with or without the OEM diffusers in place, and feature Viton O-rings for boosted applications.
Fuel Injector Compatibility
- Injector Dynamics ID1050x — 34-14-14
- Injector Dynamics ID1300 — 34-14-14
- Injector Dynamics ID1750 — 34-14-14
- Injector Dynamics ID2600 — 34-14-14
Note: Fuel injectors are not included and must be purchased separately.
Features
- Top feed conversion design for 13B-RE / 13B-REW rotary engines
- Large internal bore for high-flow fuel delivery
- 3x 8AN ORB ports — centre port for accessories (FPD, pressure transducer, temp sensor)
- Black anodised aluminium — E85 and all fuel type compatible
- 14mm lower injector seats with Viton O-rings — OEM diffuser compatible
- Phenolic thermal insulating spacers and washers included
- Stainless steel mounting hardware included
Part Number:
- 20-0445 — Radium Top Feed Conversion Primary Fuel Rail (Mazda RX-7 FD3S / Cosmo, 13B-RE / 13B-REW)
Why Radium Engineering?
- ✅ Manufactured in the USA to motorsport-grade tolerances
- ✅ CNC-machined billet aluminium components built for performance and longevity
- ✅ Trusted by high-power build tuners and race teams worldwide
- ✅ Bolt-on fitment — no cutting, drilling, or fabrication required
- ✅ Compatible with E85, pump petrol, and flex fuel sensor integration
