This fuel rail has been confirmed to work with the following Honda engines: H22A1, H22A4, H23A1, F20A, F20B, F22A1, F22A4, F22A6 However, there are likely many other variations that are compatible. And even though the Radium Engineering fuel rail has 3 fuel rail mounts, it will work on many of the 2-bolt intake manifolds Manufactured with a large internal bore, the fuel rail can support all necessary engine power requirements. They are CNC machined from 6061 aluminum, anodized, and laser etched for a high quality surface finish. Like the OEM fuel rails, the injector bores are 11mm ID so factory injectors, or any equivalent aftermarket injector, can be used.