Fuel Pump Direct Feed Rewire.

[89CAL]

Did you use the negative (gray) from the wiring loom as well or just the 12v blue?

Cheers

think I just went straight to ground as I wasnt sure if the feed from that is earthed through the ECU when it requires full pump flow (becasue they have the drop resistor setup etc)

So it works flat out all the time. Not 100% sure this is how I did it, but dont see a problem with doing it like that. Its only a trigger wire after all, not flowing masses of Current or voltage

Edited April 15, 2013 by 89CAL

[SiR_RB]

ok I just had a look at my fuel pump wiring setup and ive got 12gauge cables running directly from the battery in the boot to the relay and to the fuel tank lid,

would anyone know if this is sufficient? the cable is thicker then the cables the walbro pump came with, also running a 30amp fused relay and inline fuse at the battery

not sure if its thick enough or should I re do everything with 8gauge cable?

[Behind Horizon]

So is it necessary to ground the fuel pump close to the battery? Or is it sufficient to ground it to the chassis close to the fuel pump?

Furthermore what is the minimum fuse and relay size? 15A?

I will use a Supra fuel pump.

[Hanaldo]

ok I just had a look at my fuel pump wiring setup and ive got 12gauge cables running directly from the battery in the boot to the relay and to the fuel tank lid,

would anyone know if this is sufficient? the cable is thicker then the cables the walbro pump came with, also running a 30amp fused relay and inline fuse at the battery

not sure if its thick enough or should I re do everything with 8gauge cable?

I realise this is a late reply, but in case it is of any benefit to others.

12-gauge cable isn't big enough to use from the battery to relay. I would be using 8ga as a minimum here. Then from the relay to the fuel pump, 12ga is fine. Personally I used a 60a relay, but running a 30a inline fuse.

So is it necessary to ground the fuel pump close to the battery? Or is it sufficient to ground it to the chassis close to the fuel pump?

Furthermore what is the minimum fuse and relay size? 15A?

I will use a Supra fuel pump.

Ground the fuel pump close to the fuel pump, doesn't need to be close to the battery. Minimum fuse and relay size depends on how much current your fuel pump draws, I don't know what Supra fuel pumps draw. You need to find that out.

[Behind Horizon]

Is such a rewiring for a R33 necessary as it has the battery in the boot close to the pump anyway?

[scotty nm35]

For any aftermarket pump, yes.

[Marcus89]

Is such a rewiring for a R33 necessary as it has the battery in the boot close to the pump anyway?

Having the battery in the boot makes it very easy to do

[discopotato03]

For the record N14/15 Pulsars use the same connector for their cooling fans that R33s have at the pumps tank lids connection . The Pulsar ones have the heaviest gauge wire I've seen in this type of plug so it may be better than the 33s have and not hard to splice in when doing the rewire .

I think you can buy these plugs at EFI Hardware though I'd like to buy just the terminals if available and repin them myself .

A .

[Dose Pipe Sutututu]

Rewired my fuel pump, retained the FPCM however used my own relays and a separate resistor pack. The entire factory wiring is left untouched so if my setup fails, I will have a backup to drive home etc.

http://www.skylinesaustralia.com/forums/topic/430312-r33-fuel-pump-wiring-better-feed-retaining-fpcm/page-2#entry7163251

[Mohsen]

guys im electronically retarded..
i dont know which is which on the relay lol...
need to wire it up so it comes on when the ECU tells it to.
thanks

[scotty nm35]

Old pump wires go to the coil.

New pump positive feed wire is switched by the relay, via a feed coming from the battery. Don't forget the fuse... 20 amp should do, as long as the wire is thick enough. Just splice the new feed wires in close to the tank lid.

The earth for the pump I like taking from the battery also, straight to the pump. You can earth the pump on the body somewhere if you can find good continuity, just make sure it's clean and unpainted.

[colourclassic]

ARAB (and whoever else) this is perfect for this mod, and it has the diagram on the top of the relay to make it easy:

http://www.jaycar.com.au/productView.asp?ID=SY4077

Is there any need for an FPR after this mod?

[Dose Pipe Sutututu]

ARAB (and whoever else) this is perfect for this mod, and it has the diagram on the top of the relay to make it easy:

http://www.jaycar.com.au/productView.asp?ID=SY4077

Is there any need for an FPR after this mod?

No need for FPR changes or anything, you only would need one if you cannot get the fuel pressure at 3 bar on idle (with the vacuum to the FPR disconnected when measuring pressure)

[r33canada]

could you use a headlight style fuse instead of a horn type to wire this up?

thanks

Edited May 21, 2014 by r33canada

[Dose Pipe Sutututu]

could you use a headlight style fuse instead of a horn type to wire this up?

thanks

Any fuse and fuse holder is fine. Just the correct current fuse, I.e. A touch higher than the theoretical maximum draw of your fuel pump (which will never happen unless clogged or fuarked)

[Strick.]

Gday everyone,

Have been reading through this thread working through all that is written but have a few questions. Will be doing this before i get my car tuned in a few weeks to ensure the 040 is getting all the voltage it needs to run correctly. Will rewire the pump while im at it. Car is a R32 GTS-T.

A few questions/ want to confirm:

The positive from the pump changes to white/purple. So when i cut the wire, the white/ purple from the ecu is hooked into the relay, then the new positive from the pump is hooked into the relay. Hooked into the relay as stated within the thread.

The original negative earth goes into the relay, the new earth ran from the pump is earthed to the car.

What about the original connector? Is it simply cut out of the circuit, with the sender wires just joined together? Are these the same colours before and after the plug? Can i just remove the positive and negative from the connectors, and leave the connectors for the sender wires.

This looks like the good for a relay to use with an internal fuse

http://www.jaycar.com.au/productView.asp?ID=SY4077&form=CAT2&SUBCATID=979#1

Edited August 18, 2014 by Strick.

[WantGTR]

hi guys,

just a general question. where have people been mounting their relays? in the boot close to the pump or in the engine bay?

[Duncan]

I think relays generally end up in the boot, but that's not the best way to do it because you have to run both the trigger wire and the 12v feed through the length of the car....if you mount it up front you will only have to run the 12v through the car and + trigger, -trigger and the 12v feed can all be short.

[WantGTR]

I think relays generally end up in the boot, but that's not the best way to do it because you have to run both the trigger wire and the 12v feed through the length of the car....if you mount it up front you will only have to run the 12v through the car and + trigger, -trigger and the 12v feed can all be short.

thanks for the response. this is precisely what i was thinking. ive seen loads of pics online and they all seem to have the relays in the boot. my fuse/relay box has enough space to neatly mount a relay in there so its nice and neat. i couldnt figure out if there was a specific reason as to why they are all in the boot.

its a simple wire up im trying not to overthink it!

[Craved]

if the original wiring to the pump is used as the trigger, which is in the boot, then all one needs is the new 12V direct feed to the relay then the pump.

Changing to a fused relay, the pump is fused nice and close to the end application - and can double as a kill switch without opening the bonnet