There is often confusion on what size/model injector is needed for the Mazda RX-7 FC3S and the 13B/13BT engines. Below is a list of fuel rails with the corresponding injector O-ring diameter.

For those planning on using an aftermarket fuel rail please give us a call or email, we have a few options depending on power goals and fuel type.

Injector Dynamics ID1050X injectors

FC RX-7 Injector size/fuel rail O-ring

  • 1986-1988 Mazda RX-7 FC3S EGI Series 4 (stock Rail 11mm)
  • 1986-1988 Mazda RX-7 FC3S Turbo II Series 4 (stock Rail 11mm)
  • 1989-1991 Mazda RX-7 FC3S EGI Series 5 (stock Rail 11mm)
  • 1989-1991 Mazda RX-7 FC3S Turbo II Series 5 (stock Rail 11mm)
  • 1989-1991 Mazda RX-7 FC3S Turbo II Series 5 (KGParts Rail 14mm)

Those running the oem 11mm fuel rails will use the following ID1050x injectors: 1050.11.03.60.11 RX7

Those running the oem 11mm fuel rails will use the following ID1700x injectors: 1700.11.03.60.11 RX7 

Here at Brewed we exclusively use ID injectors on all our shop builds and supported race cars. Simply put Injector Dynamics provides the best flow matching technology along with reliability under all conditions.  

The 13B is a “thirsty” engine and requires more fuel than one may expect, we often run 1050x primary with 1700x secondary injectors for up to 500HP.

Those looking for more power we recommend running 1700x primary and secondary injectors (4 x ID1700x). This is extremely important for any using Ethanol or other blends like E85.

With a range from 1050cc all the way up to 2600cc we have the Injectors Dynamic injectors to match your RX7 or 13B swapped project. 

Looking for better cooling in your 13B? Check out the Koyo Radiator for FC RX-7 from our partners over at FFrides. 

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