Radium Rotary Engine Injector Seat (Single) - Mazda RX-7 FD/Cosmo JC (13B/20B)
Radium Rotary Engine Injector Seat (Single) - Mazda RX-7 FD/Cosmo JC (13B/20B)
Universal fit
No vehicle selection needed.
This part may still fit. Check the details below or contact us before ordering. Ask about fitment
Fitment not confirmed
This part may still fit. Check the details below or contact us before ordering. Ask about fitment
In Melbourne? Fit it in our workshop.
We fit parts in-house at the RevZone workshop. Book a time and bring your car in.
Description
Radium Rotary Engine Injector Seat (Single) - Mazda RX-7 FD3S / Cosmo JC (13B / 20B)
Suits:
- Mazda RX-7 FD3S — 13B-REW
- Mazda / Eunos Cosmo JC — 13B-RE
- Mazda / Eunos Cosmo JC — 20B-REW
The Radium Engineering Rotary Engine Injector Seat is the same machined aluminium seat used in Radium fuel rails for Mazda and Eunos Cosmo and RX-7 rotary engines. It converts the OEM 16mm injector seat counterbore to the more common 14mm lower O-ring specification used by popular aftermarket injectors. The seat simply presses into the OEM injector bore and is designed to be compatible with or without the OEM fuel injector diffusers installed. It seals to the machined injector counterbore using the included Viton O-ring.
Suitable for both primary fuel injector iron ports and OEM intake manifold secondary injector ports.
Note: Most aftermarket lower intake manifolds are already machined with 14mm lower injector O-ring ports — check before ordering.
Sold individually. Quantity required per engine:
- 13B-RE — 4 total (2 primary + 2 secondary)
- 13B-REW — 4 total (2 primary + 2 secondary)
- 20B-REW — 6 total (3 primary + 3 secondary)
Features
- Converts OEM 16mm injector seat to 14mm lower O-ring specification
- Compatible with or without OEM fuel injector diffusers
- CNC-machined billet 6061 aluminium
- Type-II black anodised finish
- Laser etched logo
- Viton O-ring included — boost and fuel compatible
Part Number:
- 20-0444 — Radium Rotary Engine Injector Seat, Single (Mazda RX-7 FD3S / Cosmo JC, 13B / 20B)
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
- ✅ Press-fit installation — no cutting, drilling, or permanent modifications required
- ✅ Viton O-ring sealing — compatible with E85, methanol, and all exotic fuel types
Specifications
- Part Number
- 20-0444
- Brand
- Radium Engineering
Shipping
Orders are processed within 1-2 business days (Monday to Friday), and orders placed before 12pm AEST are usually dispatched the same day. Once dispatched, standard shipping takes 3-7 business days and express 1-3, with tracking emailed as your order leaves.
If part of your order is out of stock, we'll contact you with the option to split the shipment or hold it until everything is ready. Read the full shipping policy.
Returns
You have 14 days from delivery to request a return on unused parts in their original packaging. Refunds incur a 15% restocking fee (20% for special orders), or choose store credit and the full purchase value is applied to your account.
Parts that have been test fitted, installed, or used can't be returned, and special-order or overseas-ordered items are assessed case by case. Faulty or incorrectly supplied items are always covered at no cost to you. Read the full returns policy.