Wiring Resistors

[Reignman]

Hello,

I am in the process of installing low impedance injectors so I needed to wire in resistors. What wire going to each injector plug do I need to splice the resistor onto? I noticed that each plug gets the same, larger gauge, green and white wire and another wire that is differant color on each plug. Do I need to splice the resistor in on this differant color wire on each plug?

Thanks

[BoostFab]

the common wire on all the injectors are the power and the other color wires are the ground singals from the ecu. i recommend putting the resistor on the signal wire....you can actually put the resistor on either wire...and the impedance will be raised... use a multimeter measure the ohm and you'll see what i meant.

[DrifterTom]

i put mine on the common wire. remember that these mofos will be getting super hot. i recommend fashioning some sort of plate to mount them on. i used a piece of aluminum bent into [ and made my own resistor pack.

[Reignman]

Where did you wire the resistors in on the injector harness? Could I wire 6 resistors together add a heat sink and wire them in at the beginning of the harness (by the main plug) onto the single ground wire? Or would it be better to wire the resistors seperate off the wires running to each injector plug?

[UK-SRi]

If you mount them against each other they will run even hotter, it could be done, but you would need a bigger or better heatsink, your choice, either approach is valid.

Mike

[gawdzilla]

Where did you wire the resistors in on the injector harness? Could I wire 6 resistors together add a heat sink and wire them in at the beginning of the harness (by the main plug) onto the single ground wire? Or would it be better to wire the resistors seperate off the wires running to each injector plug?

use 6 separate resistors. you need to use something like a 10watt/7ohm resistor. Check the RB26 wiring diagram to see how you're supposed to wire it.

[Carl H]

heres how to do it right:measure the resistance of the stock injectors.measure resistance of new ones.subtract the new from the old to give the total needed resistance.for example on my motor:stock injectors ohm out at 13.5new injectors ohm out to 2.5sooooo 13.5-2.5 = 11ohmsthere for i need a 11ohm resistor, which is hard to find so a 10ohm/10 watt works fine.works a treat, i havent had any problems with my setup what so ever.

the reason that you need to run 6 individual resistors is so you dont toast a singular one that could be placed in the common feed line, with 6 injectors firing constantly it would most certianly fail.

as far as heat is concerned ive never had my resistor pack so hot as that it needed a heat sink, even after running all day at various rpms you can grab my resistor pack and its fairly cool to the touch; however adding a proper heat sink is not gonna hurt and will proly prolong the life of the resistors.

[Cubes]

I say forget the calculations. :P

Use the same ohm resistors that Nissan have used on their GTR.The GTR runs a 5.8ohm resistor pack.

Obviously the ecu has a little head room with what its drivers can handle.Start playing with resistance and you throw the lag time out.

I used an R30 Skyline resistor pack that from meory measured up as 6.2 ohms.The slight difference proves to make no difference, I have heard of some drivability issues when running the 10ohm resistors.

According to current draw calcs you WILL need 15+w resistors, I think it was actually 17w I forget exactly what my conclusion was.Decent resistors are not cheap, here in AUS it worked out the same price to grab a second hand gtr resistor pack from a jap wrecker.

With regards to wiring. Its rather simple.

One +ve feed splits in to 6, you simply wire in a resistor after this point. Or in the case of wiring in a resistor pack, you run the +ve to the resistor pack and then connect up the 6 injector +ve wires to that. Don't touch the negatives, no need. :P

BUT please to double check everything with a multimeter.
Modified by Cubes at 11:55 PM 4/7/2006