Radium Fuel Rail and Plumbing Kit | Mazda MZR / Ford Duratec (20-0503-02 / 20-0503-PK / 20-1303)

One rail family covers the MZR and the Duratec, because they are the same engine under two badges.

The Radium Engineering fuel rail for the Mazda MZR and Ford Duratec is CNC machined from extruded 6063 aluminum, black anodized and laser etched. Like the original rail the injector bores are 14mm ID, so factory injectors carry over, and provisions for the OEM injector retaining clips are built in. Four 8AN ORB ports open the door to proper AN plumbing, and thermal insulating spacers and washers are included to isolate the rail from the cylinder head. Compatible with all fuel types including E85.

Choose Your Part

• Fuel rail (20-0503-02): rail and mounting hardware, ideal for custom applications
• Fuel rail plumbing kit (20-0503-PK): adapters making the rail a direct OEM replacement
• Ford sensor adapter (20-1303): adapts the OEM Bosch fuel pressure sensor to 8AN ORB

What You'll Feel

• Flow capacity that stops limiting the engine as injectors grow
• Factory injectors and retaining clips carried over, no conversion needed
• The rail thermally isolated from the head rather than soaking up its heat
• A direct OEM replacement when paired with the plumbing kit

Features

• CNC machined extruded 6063 aluminum, black anodized and laser etched
• Four 8AN ORB tapped ports
• 14mm ID injector bores matching OEM
• Provisions for OEM injector retaining clips
• Thermal insulating spacers and washers included
• Compatible with all fuel types including E85

The Details

This is an upgrade rail, not a top feed conversion. OEM or OEM-equivalent injectors must be used: same height, and upper and lower O-rings matching the factory diameters and styles. Radium does not make injector recommendations, so consult your tuner for flow rate and the injector manufacturer for a part number with the correct dimensions.

The plumbing kit supplies the 8AN ORB plugs and SAE fitting that make the rail a straight swap for the OEM part. Note that the included fittings must be arranged differently depending on whether you are on an MZR or a Duratec; Radium's instructions show both layouts, and getting it right is what allows the OEM fuel line to connect.

The 20-1303 sensor adapter is only relevant to early Ford models that had a Bosch fuel pressure sensor mounted to the OEM rail, specifically 05-09 Focus and 05-08 Escape. Radium notes this sensor is not common on Duratec and MZR engines, so most buyers will not need it. It adapts the sensor to 8AN ORB using the factory screws and can mount on any available rail port.

Kit Includes

• 20-0503-02: black anodized laser etched fuel rail, stainless mounting hardware, thermal insulating spacers and washers
• 20-0503-PK: 8AN ORB plugs and 8AN ORB SAE fitting
• 20-1303: anodized sensor adapter base and flange
• NOT included: fuel injectors

Applications

• 2.0L Mazda MZR DOHC inline-4, commonly found in the 2005-2015 Mazda MX-5 NC
• 2.0L Ford Duratec DOHC inline-4, commonly found in the Ford Focus
• 2.3L Ford Duratec DOHC inline-4, commonly found in the Ford Focus
• 20-1303 sensor adapter: 05-09 Ford Focus, 05-08 Ford Escape

Important Notes

• Upgrade rail: OEM or OEM-equivalent injectors required
• Plumbing kit fitting arrangement differs between MZR and Duratec; follow the instructions for your engine
• Leave clearance around any port carrying a regulator, gauge, or damper