Re-wiring Your Fuel Pump

[SargeRX8]

if you run the wire feed directly from the alternator you get 14.4v

For an R33, this is a pain in the arse, but it would be an awesome method as the alternator is always off when the car is off! Dang.

[XKLABA]

For an R33, this is a pain in the arse, but it would be an awesome method as the alternator is always off when the car is off! Dang.

the factory wire on the alternator is directly run to the battery so even if car is off it still has power running backwards through it

the 33 must be diff to the 32 cause all i did was zip tie the wire to the top of the fuel line and followed it all the way to the engine bay, mounted a fuse holder to the strut tower and then across to the alternator, took about 1 hour for the hole job, you just need a set of ramps to back car onto.

although having the battery in the boot makes it alot easier and for the diff in voltage isn't really worth the effort, for me it was run wire to battery or move it 300mm over to alternator

[jimboppins2230]

Can anyone give figure gains from this mod on a stock pump? Or an estimate?

[Raven33]

Am I missing something ?

PARTS USED-

-5 x 30 AMP Fuses

-1 x Fuseholder to suit Fuses

where were the fuses used?

[BOOZTJUNKEY]

Hmmm looks like this would be a worth while diy mod

To up pressure thanks awsomE stuff

[gumflapper]

Am I missing something ?

PARTS USED-

-5 x 30 AMP Fuses

-1 x Fuseholder to suit Fuses

where were the fuses used?

yeh i dunno y u need 5 fuses

[BIT SUS]

excuse my ignorance, but wouldn't it be easier to use the negative as the trigger on the pump instead of the positive?

I'm Currently wiring in a external 044 with surge tank and manual priming button.

Fuel Pump Trigger on Pin 18 on the ECU of the RB25DET, is that a positive or a negative output?

Cheers.

[drpheel]

yeh i dunno y u need 5 fuses

not only the 5 fuses but the fuse holder is not shown in the diagram !? should it be from the Battery to the relay of from the relay to the pump !?

[RDIRTY4]

You need 5 fuses just in case a few happen to blow up in the process of installing them

It's always good to carry a few extra around with you anyways.

[gumflapper]

if your wiring shit up and your continually blowing fuses then you probably shouldnt be wiring shit up...

jus sayn...

[Cali_GTR_R32]

Hey guys I jus bought a gtr r32 stock rb26dett I was lookin to do the 12v fuel pump mod but I cnt seem to open the pics can anymore help I'm a visual learner pics would be perfect 

thanks guys ?

[Dose Pipe Sutututu]

5 hours ago, Cali_GTR_R32 said:

Hey guys I jus bought a gtr r32 stock rb26dett I was lookin to do the 12v fuel pump mod but I cnt seem to open the pics can anymore help I'm a visual learner pics would be perfect 

thanks guys ?

just ground off the earth on your fuel pump for now... no need to get fancy until you start playing around with bigger pumps

[Cali_GTR_R32]

49 minutes ago, Dose Pipe Sutututu said:

just ground off the earth on your fuel pump for now... no need to get fancy until you start playing around with bigger pumps

Why do u mean by that?

[boomtheroom]

On 6/8/2010 at 9:25 PM, gumflapper said:

see if this diagram i made helps you understand it a bit better

link to other topic: http://www.skylinesaustralia.com/forums/Fu...html&st=220

will the factory power modulate the pump under idle wired this way? i assume that it does the factory pump.. so will it pulse the relay switches duty cycle to keep pump slower at idle?

[Ben C34]

54 minutes ago, boomtheroom said:

will the factory power modulate the pump under idle wired this way? i assume that it does the factory pump.. so will it pulse the relay switches duty cycle to keep pump slower at idle?

no, not at all. you cant PWM a relay, the factory control dropped the pump speed with a resistor, this will bypass that and be full speed all the time. 

[boomtheroom]

5 minutes ago, Ben C34 said:

no, not at all. you cant PWM a relay, the factory control dropped the pump speed with a resistor, this will bypass that and be full speed all the time. 

o can you buy w modulator to run the pump at half speed all the time if current fuel needs only require that amount?

[Dose Pipe Sutututu]

15 hours ago, boomtheroom said:

o can you buy w modulator to run the pump at half speed all the time if current fuel needs only require that amount?

How many pumps do you have in your car? Honestly If you're running a single pump don't even worry about it.

 

[ChrisDC90]

Hi everyone, first post! Just joined up from the UK ?

I have just completed hard wiring the fuel pump following this guide (was a massive help so thank you for that!!) 

Only part I am unsure of and can’t see here....

The earth wire you cut, the pump side goes to the chassis as instructed, but what about the harness side from the controller?? Do I need to ground this or leave it unconnected and cover it? 

Edited August 9, 2019 by ChrisDC90