gxlspeeder

i tried using search, but for some reason my computer tells me the website is not responding every time i tried searching. so what i need to know is, what rewiring your fuel pump is, and how to do it, and what it will do. thanks for your help!

WAYNE88N/A

just the basics: fuel pump rewiring is done to compensate for the voltage losses inherent due to the resistances in the longer runs of smaller-gauge wiring present in our vehicles...got it?

gxlspeeder

i am about to get my downpipe, and then i will have a full straight pipe exhaust, will rewiring my fuel pump be enough to compensate, or should i get a new fuel pump or new injectors

RexRyder

iTrader: (10)

rewiring is fine. u can really hear it once its been rewired

NZConvertible

The why and how is explained here.

http://www.1300cc.com/howto/how2/rewire.htm

Digi7ech

iTrader: (1)

hehe I've got a NA so I didn't have to do this on my conversion.

Wayne your partially right.

It is done on TII's because the Turbo's have a function built in to drop voltage while off WOT or something like that to help with fuel consumption.

This can be bad for a midded TII since you may hit a lean spot.

WAYNE88N/A

thanks for the correction input...I kinda pulled the above out of my a$$ anyway because I personally don't agree with the rewiring mod- a lot of trouble for maybe 1 volt, and if your pump's that close to making you run lean, it's NOT the wiring you need to be worried about...

RexRyder

iTrader: (10)

TTT

NZConvertible

That's not necessarily correct. The whole point of the rewire is to reduce voltage drop between the battery and the pump, particularly when the electrical system is under load. The same mod can be done to S4 NA's (which don't have the relay resistor); it's just a little simpler. You're still feeding the fuel pump direct from the battery via a fuse and relay, which is switched by the original fuel pump wiring.

Rewiring the fuel pump this way is a very old trick that's been done for years. The relay/resistor that has to be relocated on Turbos and S5 NA's is simply an extra complication, not the reason for the mod.

You're thinking about this the wrong way. For starters, it's not a lot of trouble, it's pretty easy. That 1V might not sound like much, but dropping 1V from (say) 13V is an 8% drop in fuel pump capacity. That should be taken pretty seriously. A rewire is a bit more performance from your pump for free, and could save your engine.

turboii87rx7

i agree with NZ..... i would much rather spend the $20 or less on the rewire, rather than the $1500+ when i lean out and pop my engine. As soon as i get my new fuel pump, i am definately doing this mod. I am good with wiring stereos, so i hope i dont have a problem. That website is very nice and informative
thanks

WAYNE88N/A

point taken, NZC- but I still disagree, with concerning yourself more with the wiring than the pump when the mods to the car dictate excessive fuel flows, compared to stock

NZConvertible

It's not about concerning yourself more with the wiring, it's just another thing you can do to improve the pump's performance. It makes the safety margin bigger.

The other point is that you're trying to reduce the drop in voltage when the electrical system's loaded up. I can't remember my exact numbers now, but I know that the drop in voltage measured at the pump with everything turned on was far less after the rewire.