On newer Honda and Acura models, you'll find Electronic Fuel Injection (EFI) style fittings in many fuel system parts. They're common in returnless fuel systems, especially on the fuel rail, fuel feed hardline, and some fuel pump hangers. Our special adapter fittings quickly convert a male EFI connection to a male 6AN fitting, making it easy to switch EFI parts to a custom AN fuel system. The OEM design uses a standard plastic locking clip, and we also offer a threaded locking clip option. Both adapters have an internal dual o - ring seal to prevent leaks even under high pressure. The 1/4' adapter fits RSX and 8th Gen Civic fuel feed hardlines, while the 5/16' adapter works with all the stock EFI K - Series fuel rails we've seen. To measure your EFI fitting size, use a 1/4', 5/8, or 5/16' wrench. For 1/4 EFI Fitting, it fits 01 - 15 Civic Firewall (All models) and RSX Firewall. The 5/16 EFI Fitting is for 1996 - 00 Civic Sending Unit and K - Series Car Fuel Rail (01 - 15 Civic / 02 - 06 RSX / 04 - 12 TSX). The 3/8 EFI Fitting is suitable for 8th Gen Civic SI Sending Unit, RSX Sending Unit, and Flex Fuel Sensor.
Using these K - Tuned EFI to AN fittings is easy. First, identify the size of your EFI fitting using a 1/4', 5/8, or 5/16' wrench. Once you know the size, choose the appropriate adapter. Connect the male EFI end of the adapter to your existing EFI part and the male 6AN end to your custom AN fuel system. If your adapter has a plastic locking clip, make sure it's securely in place. For the threaded locking clip, screw it on tightly. As for maintenance, check the o - ring seals regularly for signs of wear or damage. If you notice any leaks, replace the o - rings immediately. Also, keep the fittings clean to ensure a good connection and prevent blockages. When not in use, store the fittings in a dry place to avoid corrosion.
