Radium Engineering Injector Seats – Mazda Top Feed Fuel Rails

These precision-machined aluminum injector seats allow modern 14mm lower O-ring fuel injectors to be used in rotary engine applications originally designed for 16mm injectors. Designed specifically for Mazda rotary platforms, they are compatible with both OEM primary iron ports and secondary intake manifold injector locations.

Vehicle Compatibility:

• Mazda/Eunos Cosmo (13B-RE / 20B-REW)

• Mazda RX-7 (13B-REW)

• Also suitable for rotary-powered conversions using factory Mazda iron ports or manifolds

• Not typically required for most aftermarket manifolds (already machined for 14mm)

Overview:
These seats are a drop-in solution that converts the OEM 16mm injector counterbore to a 14mm size, compatible with common aftermarket fuel injectors. They seal using the included FKM O-ring and are engineered to fit with or without the OEM fuel injector diffusers still installed. CNC machined from 6061 aluminum, they are anodized black for corrosion resistance and laser etched for a clean finish.

Key Features:

• Converts OEM 16mm injector counterbore to 14mm

• Compatible with OEM injector diffusers (installed or removed)

• CNC machined 6061 aluminum construction

• Black anodized with laser-etched logo

• Includes fuel- and boost-resistant FKM O-ring seal

• Suitable for both primary and secondary injector locations

Fitment Quantities:

• 13B-RE / 13B-REW: 4 total (2 primary + 2 secondary)

• 20B-REW: 6 total (3 primary + 3 secondary)

Sold Individually – Order the appropriate quantity based on your engine configuration.