Radium Engineering Fuel Rail | 1989-1993 Mazda Miata (20-0769-02)

The NA 1.6's fuel rail was sized for 116 stock horsepower, and turbo Miata math left that behind decades ago.

The Radium Engineering Fuel Rail for the Mazda 1.6L B6 gives the early Miata a rail worthy of its aftermarket: CNC machined from billet 6061 aluminum, black anodized and laser etched, as a direct replacement for the OEM fuel rail with four threaded ports all tapped 8AN ORB. The 11mm ID injector bores match OEM so factory injectors carry over, the OEM plastic spacers reuse to thermally insulate the rail from the aluminum intake manifold, and every fuel type including E85 is welcome. This is the rail-only kit for custom fuel systems; the 20-0769-PK plumbing kit (sold separately) covers factory-plumbing installs.

What You'll Feel

• Fuel delivery headroom for the turbo kits and ITB builds the NA 1.6 attracts
• Four 8AN ORB ports opening regulator, damper, gauge, and custom plumbing choices
• Factory injectors reinstalled directly in true 11mm OEM-spec bores
• Manifold heat kept out of the fuel via the reused OEM thermal spacers
• A rail that fits far beyond the Miata, across Mazda's global B6 family

Features

• CNC machined billet 6061 aluminum, black anodized, laser etched; direct OEM rail replacement
• Four threaded ports, all tapped 8AN ORB (3/4"-16)
• Upgrade rail: 11mm ID injector bores; factory or OEM-equivalent injectors only (matching height and O-ring dimensions and styles)
• Reuses OEM plastic spacers for thermal insulation and factory mounting hardware
• All fuel types including E85
• Rail-only kit; fittings and plumbing kit (20-0769-PK) sold separately

The Details

Radium's upgrade-rail rule governs injector plans: OEM injectors drop in, and upgrades must be OEM-equivalent in height and O-ring specification, with flow rates from your tuner and dimensions confirmed by the injector manufacturer, since Radium specifies nothing beyond OEM equivalent. The four-port layout turns the little rail into a real platform, with feed and return through ORB adapters and the remaining ports hosting a direct-mount regulator, pulse damper, or gauge adapter; Radium's standing advice is to leave ample space around ports destined for larger accessories, checking the dimensional drawings for clearance. Factory-regulator installs should pair the rail with the 20-0769-PK, which retains the OEM regulator and feed/return hoses for a bolt-in job.

Kit Includes

• 1x Black anodized, laser etched billet aluminum fuel rail
• Factory mounting hardware and OEM spacers are reused
• Fittings and plumbing kit (20-0769-PK) sold separately

Applications

• 1989-1993 Mazda MX-5 Miata and Eunos Roadster (1.6L B6)
• 1993-1999 Mazda Xedos 6, 1997-2003 Familia and Etude
• 1997-2004 Kia Sephia, Shuma, and Spectra
• Factory or OEM-equivalent injectors only