DIY: Fuel pump upgrade and hard wire

So I had recently completed a myriad of upgrades on my S14, with one of them being a fuel pump upgrade. I had decided to change to a Walbro 460lph fuel pump, which is recommended to be run in conjunction with a hard wired power supply direct from the battery.

The old boot table trick

Parts required: 

- 6m of power cable - I went 6mm 50A since I'm running a 30A relay

- 1m of ground cable - Again 6mm 50A

- x1 Narva 68060 30A fused relay

- x1 Narva 56088BL (12pk ring terminals) (If you're using 6mm wire)

- x1 Narva 56045BL (12pk female spade terminals) (Again if you're using 6mm wire)

- In line fuse

- Soldering Iron & solder

- Heat shrink or electrical tape

- Flameless heat source if using heat shrink

- Fuel pump that warrants a hard wire

Recommended:

- Some gloves

- Fairly low fuel level

- Rags

So before you begin, I recommend that you clear out your fuel lines by pulling the fuel pump fuse and turning the car over (I recommend this because I forgot to do it). Pull back the carpet above your fuel pump and you should hopefully see the cover. Simply remove it using the appropriate tools.

This photo is probably unnecessary

Mark your fuel lines and disconnect them. If you've cleared your fuel lines properly it shouldn't spill out like it did for me whoops. Then just tap the locking ring off using a screwdriver and hammer unless you can hulk it off by hand which I highly doubt.

Tap  tap tap

 Remove the cradle by simply pulling it out. This is where having a low amount of fuel would help so your arm doesn't have to go swimming in fuel.

Hello

The previous owner had a Bosch 040 fitted. The new Walbro 460 is smaller, pumps out more fuel and is also much quieter. I had to splice the new connector on which is fairly straight forward and I just heat shrinked over the joins.

I secured the new pump using a combination of zipties and hose clamps.

She'll be right

The Wiring:

So for the actual wiring of the fuel pump, I worked this out:

-PIN 30 - 12V from battery

-PIN 85 - Ground

-PIN 86 - Positive wire from OEM fuel pump wiring

-PIN 87 - Power to fuel pump

Crimp a ring terminal onto one end of your power wire and connect it to your battery terminal. It's recommended to have a fuse near the battery as Evan advised me a short in the wiring could cause a fire before the fuse at the relay will pop.

Then simply run the wiring through the car to your boot. There's a grommet near your clutch MC in the firewall that you can run it through. Otherwise you can run it through where your chassis loom goes otherwise if there's not enough room in that grommet, you can feed it through where the body loom goes like I had to.

Nice and neat

So once you have the wire through, cut off the excess into the smaller pieces you'll require and crimp the required terminals onto the ends of them. For the OEM fuel pump wiring, it'll be a plain black cable (ground) and a black cable with yellow stripe (positive) that you'll cut in half and splice your necessary wiring into. Follow the list I posted earlier (the ground half that goes from OEM wiring loom -> fuel pump just cap off with some extra heat shrink or tape it off as it's now redundant).

For the actual grounding, sand away the paint on a nearby hole and run a hex screw or nut and bolt through it with some washers.

Label your wires to make it easier to identify in the future if you need to replace the relay. I also mounted the relay on the side of my boot and it's been advised to mount them vertically too. I used velcro and a zip tie lol. 

So after you've refit and connected everything, turn the key and pray it starts. If it doesn't then check over your wiring and fuses and if that all seems fine, then pray and message your preferred auto electrician.