MSD 72# Injector Resistor Instalation [Archive] - SR20 Forum

: MSD 72# Injector Resistor Instalation


NX$paniard
03-26-2004, 01:14 AM
Hello folks I am getting ready to throw on the 6.8 Ohm resistors for my MSD 72# injectors onto my NX (B13). I was wondering if any of you guys know off hand or could find the color/locations of the wires to where the resistors need to be soldered into at the ECU. I could probly figure it out if I had my FSM, but its at the machine shop at the time, and Im trying to get all my wiring done before the engine is ready.. Hope someone can help (not to mention it might be good info for the Turbo FAQ section). Thanks in advance....

coach
03-26-2004, 01:48 AM
I thought you soldered them on at the fuel rail, right inline with the new injector clips. What i did was pick the same wire color code for each injector and that worked fine for me for wiring my MSD's.

Brent

unlucky
03-26-2004, 02:01 AM
I put them right at the ECU connector.. cut it about 3" off of the harness plug.. and put them in there.. I solder/shrink wrap each one.. and then make a block with the 4 resistors.. and tape them all together... making sure to take the 4 strands together.. This makes is stronger. I think the wires are yellow, blue, green and red. They will have a black stripe too I think. I need to check..
Travis

NX$paniard
03-26-2004, 09:46 AM
awesome!! let me know when u know the colorers for sure, i do appreciate it!!

Wicked R
03-26-2004, 05:59 PM
Travis-

Did mine ring a bell?? :P

Cheers-
Erich

Justin
06-19-2004, 04:39 PM
awesome!! let me know when u know the colorers for sure, i do appreciate it!!


So how did you end up wiring them man?

sr20veb13
06-19-2004, 11:59 PM
hey guys dont mean to bite on the thread but, i have the 72lb injectors, and i dont really know what the resistors are for? could you explain

Justin
06-20-2004, 12:25 AM
hey guys dont mean to bite on the thread but, i have the 72lb injectors, and i dont really know what the resistors are for? could you explain

You have the injectors installed and running with no resistors? I didnt think that was possible. You have to wire in a dropping resistor to drop the ohms to work with the MSD's.

sr20veb13
06-20-2004, 01:28 AM
You have the injectors installed and running with no resistors? I didnt think that was possible. You have to wire in a dropping resistor to drop the ohms to work with the MSD's.


no there not in yet . there just sitting in the rail... ive got my jwt coming shortly.. i guess i will do a search because i know nothing about the resistors, where they go, or anything. happy i read this because i would have hooked them up and not known about the resistor

Justin
06-20-2004, 11:59 PM
So....

How does everybody do their's? At the injectors, or at the ECU? Which is easiest/or better?

NX$paniard
06-21-2004, 11:52 AM
Its best at the ECU, obviously because they are wire wound resistors (old fashioned), so its best to keep them away from heat and the elements. I eneded up wiring mine to the wires that were the same color as the injectors. They are on the ecu bundle on the passenger side. i individually wrapped each one, then wraped them all together. I am pretty sure that is the way, and several people have said "it sounds right" how funny that nobody will actually confirm this as if its some sort of secret. Ill let ya'll know if tis right when my engine runs, but that may still be ways away.,.. :(

SENTRA1909
01-30-2005, 07:02 PM
does anybody have a set in stone answer on what color the wires are? and are they the same for the diffrent years?

I dont mean to bring back an old post but, I am going out to the car to put in the resistors tonight and am hoping that I cut the right wires... B13 91 wire harness...

Justin
01-31-2005, 04:22 PM
does anybody have a set in stone answer on what color the wires are? and are they the same for the diffrent years?

I dont mean to bring back an old post but, I am going out to the car to put in the resistors tonight and am hoping that I cut the right wires... B13 91 wire harness...


I figured them out and put them in a B14 in October. I would have to actually go look to recall them. I believe that they are different for different cars (B13 and P's are diff I think).

boostn92se-r
01-31-2005, 05:03 PM
If I had my car in front of me I would tell you but on mine there is a white wire on all of the injectors and the other wire goes to the ecu I cut those wires for the resistors it was like black/red stripe, black/yellow stipe, black/green stripe. Just go to the connector of the injector and the color that is not the same on all four is the one that I tapped into.

NX$paniard
01-31-2005, 05:27 PM
Justin


Didnt you just end up doing what I did except on a B14 (matching the colors of the injector harness to the ones @ the ECU and putting the resistors inline w/ those 4) ?

Also for thge guy that asked what they are for.... the answer the other guy gave is WROOONG!! how does ADDING resistors DROP the "ohms" (ghetto term for resistance/Impedance)

Our ECUs are set for use w/ HIGH IMPEDANCE injectors. The 72# Injectors MSD/Delphi makes are LOW IMPEDANCE. By ADDING 6.8 Ohm resistors onto the LOW IMPEDANCE injectors makes them HIGH IMPEDANCE and the ECU thinks everything is grand :)