The fuel rail ports are tapped for 8AN ORB.
This Radium Engineering secondary fuel rail is for the Mazda 13B-REW rotary engine.
With the use of the provided 2AN ORB plugs, this adaptable design permits both the OEM 2-port intake manifold (shown above) and aftermarket 4-port intake manifolds (shown below).
The aluminum fuel rail is anodized black for compatibility with all popular fuel types including E85. Manufactured with a large internal bore, the fuel rail can support all necessary engine power requirements. The three 8AN ORB ports are compatible with these fittings HERE. The extra center port allows additional fuel system accessories such as the OEM fuel temperature sensor (using 14-0421 shown below), a pressure transducer, Radium fuel pulse damper, etc.
Insulating spacers and washers are included with stainless steel hardware to prevent thermal energy from conducting heat into the fuel. The two M8 extension mounts are made from stainless steel for superior strength and corrosion resistance.
For the OEM 2-port intake manifold, the included 20mm insulating spacers, billet injector seats, and 2AN ORB plugs will be used. Also, for the required space, an air control valve delete for the OEM 13B-REW intake manifold (sold separately) is required. See Radium 20-0449 HERE.
The included 14mm lower injector seats were designed specifically to be compatible with or without the OEM diffusers in place. They feature FKM O-rings making them suitable for boosted applications. NOTE: if using an Elite Rotary Shop 4-port intake manifold (shown below), 2 extra injector seats are required which can be purchased HERE.
With this fuel rail, all lower intake manifolds variations are compatible with the fuel injectors listed below. For the Xcessive Manufacturing 4-port intake manifold, the included 11mm insulating spacers will be used.
FUEL INJECTOR COMPATIBILITY
Below are some of the many fuel injectors that are a direct fitment with this fuel rail: