Eight Nine 6AN Return Fuel Line Kit for Mazda MX-5 NB 01-05
The 01-05 Mazda MX-5 has a returnless dead-head style fuel system with a damper on the end of the fuel rail instead of a pressure regulator—which would usually bleed excess fuel off into the tank. Whilst the 01-05 NB has a base fuel pressure of 4.0 Bar, due to the lack of a regulator at the fuel rail each PSI of boost reduces the fuel pressure by the same amount. This means that it is only really possible to run 1.0 Bar or 14.5 PSI of boost pressure before the fuel system should be upgraded to a return style system.
We’ve developed this kit to replace the vent tube that runs from the tank to the charcoal canister which allows us to utilise the connection on the top of the fuel hat to return the excess fuel to the tank. All fuel hose is E10/E85 compatible to ensure it will last the lifetime of the vehicle.
The standard damper is replaced with a 6AN adapter to allow a return line to be taken straight from the end of the rail to the tank. We strongly recommend replacing the whole hard line with 6AN hose. Whilst the hard-line can cope with returning the appropriate amount of fuel at full throttle, it is not large enough to return the required volume of excess fuel at idle, which can cause poor running.
Simply add the fuel pump and fuel pressure regulator—with 6AN barb fittings—of your choice to unlock the horsepower potential of your setup.
Kit contents
- 3 x 6AN to 8mm OEM quick connects
- 3m 6AN Teflon braided stainless steel
- 30cm Gates submersible fuel hose
- 2 x 6AN fuel rail adapter
- 4 x 6AN 90-degree fittings
- 1 x 6AN 90-degree forged fitting
- 1 x 6AN straight fitting
- 1 x 6AN to 8mm hose barb