2 s4 low impedance and 2 s4 high impedance wired on the same harness
#1
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2 s4 low impedance and 2 s4 high impedance wired on the same harness
I was wondering if there was a way I could do this. For some reason I've acquired 2 s4 low impedance injectors and like 8 s4 high impedance injectors. My car is low impedance, NA. These are the last thing I need for it to run and I was wondering if there was a way to use 2 of the high impedance injectors along with 2 low impedance injectors. I've read a few threads about using either full high impedance or full low but nothing about mixing them up. I would really like to get this car running tomorrow because my S13 needs to come off the road asap otherwise I would source out 2 low impedance inj. but I just don't have the time.
#3
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Like mentioed above. Go to the plug on the resistor pack.
Remove the metal cover from the resistors and wires.
Determine which of the two wires go to the injectors your interested in.
Go to the BOOTS (see jpg) of those two wires and pull the boots back and desolder those two wires from the resistors.
FYI: the middle wire is the power wire and feeds the solenoids at the place I named the BLADE in the jpg.
So take those two wires you just desoldered and solder them together with a NEW piece of wire. Then protect them with either shrink tubing or electrical taps so they can't short to the metal case. You select your own method of doing that.
Take the other end of that NEW wire and solder it to the BLADE.
Your more or less done. See jpg of what I called BLADE and BOOTS.
How to determine which two wires? See your local 86-87 wiring diagrams. But...the front primary is BROWN and the rear primary is BROWN/RED.
Those colors are on the HARNESS side of the plug, not on the resistor package side of the plug.
Of course there's other ways other than the above. You could go to the harness side of the plug. Extract the two wires your interested in leaving their contacts on the end of the wires. Then solder those two together. But now you need to feed them 12v from the black/yellow wire that's still in the plug. Hmmm. You could then cut the black/yellow wire a couple inches back from the plug. Then solder both *halves* of that black/yellow wire to the two wires you previously soldered together. One big fat happy bunch of wires I suppose. But would work if covered in shrink tubing and or electrical tape to prevent shorts to gnd.
EDIT: I say to depin the two wires leaving the contacts on the end of the wires. That's so if you later in life go back to the original injectors, all you have to do is unsolder the two wires and reinsert them into the plug. Back to normal then.
Remove the metal cover from the resistors and wires.
Determine which of the two wires go to the injectors your interested in.
Go to the BOOTS (see jpg) of those two wires and pull the boots back and desolder those two wires from the resistors.
FYI: the middle wire is the power wire and feeds the solenoids at the place I named the BLADE in the jpg.
So take those two wires you just desoldered and solder them together with a NEW piece of wire. Then protect them with either shrink tubing or electrical taps so they can't short to the metal case. You select your own method of doing that.
Take the other end of that NEW wire and solder it to the BLADE.
Your more or less done. See jpg of what I called BLADE and BOOTS.
How to determine which two wires? See your local 86-87 wiring diagrams. But...the front primary is BROWN and the rear primary is BROWN/RED.
Those colors are on the HARNESS side of the plug, not on the resistor package side of the plug.
Of course there's other ways other than the above. You could go to the harness side of the plug. Extract the two wires your interested in leaving their contacts on the end of the wires. Then solder those two together. But now you need to feed them 12v from the black/yellow wire that's still in the plug. Hmmm. You could then cut the black/yellow wire a couple inches back from the plug. Then solder both *halves* of that black/yellow wire to the two wires you previously soldered together. One big fat happy bunch of wires I suppose. But would work if covered in shrink tubing and or electrical tape to prevent shorts to gnd.
EDIT: I say to depin the two wires leaving the contacts on the end of the wires. That's so if you later in life go back to the original injectors, all you have to do is unsolder the two wires and reinsert them into the plug. Back to normal then.
#4
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I've been running a box that has the resistors disabled in the secondaries for over 5 years now. The desolder then solder method is the way to go, plus it is very easy to undo if you need to go back. Just follow Hailers advice in post #3 and you could set it up just as you wanted.
#5
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OOOOPS. the wires are crimped to the resistors, not soldered. Big deal.
So I just cut two wires right at the crimp.
Then got a 14ga crimp and burned the insulation off it. Crimped the wires to it. If it were me I'd crimp them and solder them , but this is just for fun.
Then ran the yellow wire from the crimp to the end of the package and soldered it to that end.
You'd want to insulate the crimp with??? shrink tubing from RS or the auto store and tidy things up a bit. But this is what I was trying to describe in the other post.
First jpg is of an unaltered package. Second jpg is the cover off it. Third jpg shows the two wire cut at where they were crimped on the resistor. Fourth jpg is the wires crimped and soldered.
That should work. But as to which two wires have to be cut and tied together depends on which of the two injectors are high impedence.
So I just cut two wires right at the crimp.
Then got a 14ga crimp and burned the insulation off it. Crimped the wires to it. If it were me I'd crimp them and solder them , but this is just for fun.
Then ran the yellow wire from the crimp to the end of the package and soldered it to that end.
You'd want to insulate the crimp with??? shrink tubing from RS or the auto store and tidy things up a bit. But this is what I was trying to describe in the other post.
First jpg is of an unaltered package. Second jpg is the cover off it. Third jpg shows the two wire cut at where they were crimped on the resistor. Fourth jpg is the wires crimped and soldered.
That should work. But as to which two wires have to be cut and tied together depends on which of the two injectors are high impedence.
#7
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Bypassing the solenoid resistor package is done as shown in the attached jpg........if installing all four high.
The only improvement to that jpg, is that I'd take a torch and burn off the insulation on the yellow crimp connector (takes three minutes and comes out clean with no residue plastic). Then crimp And solder the wires to it. Then cover it with shrink tubing.
The only improvement to that jpg, is that I'd take a torch and burn off the insulation on the yellow crimp connector (takes three minutes and comes out clean with no residue plastic). Then crimp And solder the wires to it. Then cover it with shrink tubing.