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Rumnhammer

Chris Rummel's easy follow RB into Z wireing guide

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Chris, what is the exact role this brown plug plays on the rb alt.? I just wired up my RB starter and alt using the stock 74 Z harness connectors. Everything seemed to be fairly easy, except I don't know what to do with the white T plug, left over on the Z harness that plugs into the Z alt.

 

I assume the white T plug on the Z harness, for the Z alt. serves the same function as this brown plug (as shown in pic below) on the RB alt. harness? Do I need to even use it if I'm using all after market gauges (no volt meter)?

Can you give me some guidance please... joel

 

RBZwire027.jpg

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Z U L8R    10

hey chris,

my 78 280 + rb20 was cake, from the big grey skyline plug i had to make 2 wires ignition power and one constant, then i spliced in the alternator big to little and little wire to big wire, basically white/red to white/red, the oil pressure sender has 2 wires just like the 20 and the starter's self explanatory, i didn't use the rb lower harness i just changed the plugs on my 280z's and voila, the wiring was simple.....

 

now i'm on my friend's 71 240z + rb25det, #1 his wiring harness only has 1 relay, and it looks like individual ignitors on each coil pack which is why i'm assuming it only has one relay, so my problem is wiring in his white dash plug and integrating that into the ignition switch which if you can break down what wire #/color from the dash plug needs constant, ignition, start, and ground from the ignition switch/chassis that'd break it down a lot simpler for me. i'm pretty sure of myself but i'd like a second opinion. if you want me to post my thoughts first and see what you think i can do that too. the way i see the plug i wanna be like "aiight this wire needs constant 12v, these 2 get ignition power, ground this one, and this one gets the start signal"

thanks

David

 

here's another breakdown for the external voltage regulator bypass

http://www.zcarcreations.com/howto/voltreg.htm

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Funny thing is, I had a post this A.M. in this thread, asking the same exact thing about hooking up the rb alt.

 

I wasn't 100% sure what to do with the T plug thats on the Z harness for the alt. I ended up splicing the brown plug off the rb lower harness onto my Z harness.

 

I had so much junk stuff I deleted from the Z engine bay (shunt, voltage reg, seatbelt interlock, etc.) which left plenty of un used plugs and connectors hanging....

 

I just hooked up the rb alt using the Z harnesses connections, and the starter the same way. I hope to get power to the starter/ alt. just like if it were the Z parts.

 

Since I'm using a Tec2 standalone ign, and all new electrical AutoMeter gauges, I should not have to much trouble getting the starter and the alt to work. The rest is all new rewire anyways. I'm soooo close to starting her up.... :willy_nil

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Rumnhammer    20

Ok, it sounds like you have a differnt series RB25 then I had. I have the first series 1. It only has the one ignitor, for the individual coil packs.

You may have a R34 series I believe these are slightly differnt and likely have a different pin out on the ecu. Basically if you know what wires you are dealing with, you should be able to hook them up similarly to what I posted in this sticky. Even though the wires may be going to different pins on the ecu then mine, if you chart them as to the function, then it doesn't matter what color they are or # they are. if that makes sense??

 

So if you match the function with the wire in the sticky it should work.

Oh, and that Z car creations alternator regulator guide was totally wrong for my application, the sensor wire on my car went nowhere, and the hot went to ground on the 75 zcar, which is why I ended up doing it my way for that step.

 

You can, primarly use the Z car lower harness, instead of splicing it into the RB, (Q did his car this way) I spliced mine in because I wanted it as plug and play as possible, and also the AAC valve wiring is on the lower RB harness as well, so you at least need to run the wires for that separatly if you use the majority Z car lower harness.

Chris Rummel

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Z U L8R    10

yeah, thanks chris :-D. i've been making headway on my friend's wiring he has a series 2 rb25det, ours with the 1 external ignitor is series one, these both have vtc, the neo motors as far as i understand came out of r34's and have a bunch of plastic crap on em, like popping the hood on one of today's newer nissans here, that's the answer i got when i was asking some jdm engine venders if they've ever came across a 25 like my friend's.

 

so far as far as the dash plug goes the only wire that's not there is the solid big red one that goes to the ignition relay because he only has an ecu relay. we're gonna cut a bigger hole through the firewall tomorow and feed the ecu harness through then get started on wiring it to the ignition switch etc. but so far since i'm not just reading, i'm doing as you're explaining, everything's running smoothly and it makes sense EXCEPT for what's making me smoke more cigarettes than usual LOL, the external voltage regulator removal.

 

the reason why is everyones' plug in the world is round except his, he's got the bastard child rectangle plug which was throwing me off and as it is this is my first external VR project. honestly, tonight is the first time i've been able to find a wiring schematic for the theory and operation of the thing so i can comprehend it and not just pray as i take his rectangle plug and wire the thing based on wire color while imagining the plug is round lol. So now i'm in the "ooOOOOo i c" process and it's making a lot more sense. This is the first place i've seen mention of the rectangle plug, check this, tell me what you think.

 

http://www.atlanticz.ca/zclub/techtips/alternatorswap/index.html

 

the only thing i'm still searching is cutting off the T shaped plug on the alternator and splicing in the rb's without mixing up the wires (i think J Soileau is seeking the same info), or checking voltage with a volt meter to determine which goes where when the car's not running in the first place lol it's only 2 wires i know someone here knows it right off hand LOL, basically the rb's plug has 2 wires, one is white/red stripe the other is blue & something i forget, and i'm searching for the answer

 

ie

 

"white/red goes to "S" and blue goes to "L" <----[that's my guess. i'll check my 280z rb20's plug/wire colors tomorrow and pray the 25 has the same colors]

 

Can anyone confirm that though?

 

Once i get that confirmation i commence "I GOT THIS! WHO'S YOUR DADDY" phase ^.-

 

all in all so far so good though chris, i really appreciate all you guys helping and so does my friend.

David :-D

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Rumnhammer    20

David, look at the posting in the sticky at the alternator wiring, the last link you posted was far superior to the Zcar creations one, notice in the 1975 wiring, it is supposed to have a green/red stripe wire? Mine didnt' have that, so I did a very basic convertion.. It really doesn't matter what shape the connector on the VR is because really you don't need to worry about most of the wires going to the VR. Going from the wires at the alternator, the white/black stripe wire that goes to the L connector on the alternator gets connected to a good "on when hot" really can be any one, I just ran one out to the engine compartment and through the hole where the green/red wire was supposed to be, the white/black wire then goes down to the alternator, where you will need to wire in a diode like I show in the pic, this is like a one way valve that keeps the engine from continuing to run after turning off the key. You will need this if you are using the RB alternator because it is 90amp.

The Yellow wire you can splice into the RB wire in my case was light green that goes to the RB S terminal on the alternator, this wire you run right to the main battery terminal. That is really all you need to know about the VR removal, I hope that clears it up a bit for you.

Chris Rummel

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Z U L8R    10

thanks :D

 

well...on to series 2 variation number 2. the thin grey wire that goes to the 8 pin skyline plug off the maf harness doesn't have the grey wire in it to feed ignition power to the fuel injectors from there. So i'm just gonna tap into it at the injector goofy lookin 8 post plug cause it does have the wire there.

 

i pulled a green efi relay from one of my old 240sx's and i'm gonna use that for his fuel pump relay and wire that in tonight as well as bypassing the voltage regulator. then all we have to do is recirc the heater hoses, and do all the intake hose routing (he has a jun intake manifold) then we'll sit the motor in, get the fluids in, and crank it up.

 

he's running a t3/to4e which is already on, and he has some 550's but for now i left in the stock injectors so we can just make sure the thing idle's and such, he still needs to get a z32 maf and i've already wired in the safc2, but the car should still start up without a maf.

 

oh i have one more question, i've heard you wanna disable vtc after 400hp...did you already post how to wire that in though? *i'm being lazy :P

 

thanks for all your help.

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Z U L8R    10

well....with no intercooler piping, no mass air flow, no radiator, no exhaust, no 02 sensor and the fuel return line going into a gas caddy the rb25 started right up. :D we got more to do but at least we know the motor'll run and idle on it's own. thanks a lot Chris for your write up, it helped immensely, and all my questions got answered as i went on. thanks again cause as soon as i'm done with my friend's i can yank out my rb20 and do my 25 swap in a day or two :D

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AMV8(1day)    10

Hey chris, I frequent this site more often but I happened to see one of your threads on this on GRM and noticed you're from Baltimore, I'm originally from the Catonsville area and am now back in MD living in the Odenton area.

Anyway, I'm getting ready to start a RB25-'77 Z swap and saw how clean and professional your friends engine bay was after you finished and was wondering if I could come by and bug you about it. I'm looking at picking up a NeoGen RB25 engine, tranny, and LSD and really want to find out what I'm getting myself into before I order the engine and find out I'm giong to need the whole front clip.

Thanks

 

 

Joseph Kacvinsky

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Rumnhammer    20

Hey, Joe you are more then welcome to come over and check out the RBZ, as it is still in my garage, much to my shigrin:icon_frow I would also be happy to help you out in any way possible.

 

I did all the custom fabrication myself. in my little shed.:-)

 

email me directly or pm on here and I'll give you my address, etc.

Chris Rummel

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AMV8(1day)    10
hey AMV8(1day) are you getting your motor locally? If so where at? The only place i've seen close is japaneseengineimport in sterling va.

Hey loy,

Sorry I didn't respond sooner but I had written out an entire detailed message about where I am most likely giong to get it and all the other places I found in my search. But apperently I didn't send it or something sense its not here, so I'll see about writing another one when I get some time at home where I have all the info. Meanwhile, I'll just say that I am talking to the guys over at JDM-online.com about a NeoGen engine, tranny, and LSD.

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Z U L8R    10

Chris,

We discovered one of his coil packs wasn't working. And being a series 2 it doesn't already have an external ignitor, so I wired in a PTU from a Z32 and wired in a Grand National Coil /w msd ignition cables. I've noticed all the guys in Australia with 800+hp run this wasted spark set up, if you're interested in how to do it, I'll let you in on it since you've been such a help to me. Thanks again ;)

David

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Z U L8R    10

Also be very careful about using the tach adapter. I believe the stock Z guage wants a 12v signal but if you have an autometer or other aftermarket tach that wants a negative pulse as the signal then you don't want to use a tach adapter. basically the tach adapter takes the negative signal and converts it to a 12v signal.

 

his autometer wanted a ground as the signal so before i read up on the tach adapters job i actually fried out the 52 ohm resistor in his ecu for the tach signal, which left me pissed about how the hell he was gonna get the safc2 tuned without the safc being able to read rpm. at which point i ran the safc2 to the 120degree cam angle sensor ecu pin, which there is 2 of, either green wire should work but i believe i used the 40 something one, i think it's 41 but i don't feel like checking the pinout right now. discarding the tach adapter altogether i spliced in his autometer guage and safc's green tach signal wire into that 120 ecu pin and voila.

 

my caution is to see if your particular autometer tach wants a 12v as the signal or a ground, cause i'm sure they make both. in the guage box there should be instructions that'll tell you. his had something on the back of the instructions that said "for old style ignition systems" and it had a picture of the signal wire going to the negative post on the external coil.

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alexideways    12

I also have a series 2 engine, after quite a bit of searching the net, I finally determined, with my ECM P/N (23710 13V00), that the engine came from an 1996 Gts-t.

 

I also have only one relay.

 

One more thing is, in my harness, I only have 1 white dash plug.

 

Like Z U L8R, I don't have the big red wire in my dash plug.

 

I went one step further and chased down all the unused wires and removed them fom the harness.

 

I was left with 1 grey, 3 prong plug that goes in the TPS, I guess that was used for the cruise control as none of it's wires went to the ECM.

 

I also eliminated the wires that were spliced in other connections to simplify futur diagnostics.

 

 

I was also left with a black box marked:"AMP ASSY. WIPES, P/N 28510 26V00" and a 6 prong, white connector with 5 wires in it, all of this ended up being connected to nothing. I laso separated all the unused wires that came fron the dash plug to the ECM but, hav'nt cutted 'em off yet as I wan'a make sure of there function before I remove them entirerly.

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Z U L8R    10

:D, basically i followed chris's lead, everything started smoothing out once i was working on it at the same time i was reading what he was saying, but my friend's 8 pin skyline plug where you spade connect the grey wire that ends up feeding the injectors 12v wasn't in that plug, instead of a typical 7 it only had six, so i traced the schematics and tapped it in to the funky shapped big grey plug that actually plugs into the injectors' harness, and powered it to the now thick grey wire right there and had no problems.

 

he ended up having a bad coil pack on cyl 1 so i also wired in an ignitor from a z32 and wired in the wasted spark set up buick grand national coil with msd 8.5mm spark plug wires. it's sexy :D. he still has his series 2 coil packs in which 5 are good so if you run into a misfire when you're all done he'll probably sell you a replacement for a fair price.

 

basically for now don't worry about the thick red wire, just follow chris's lead and power up the injectors and you should be fine. ya there should be a fake plug with no wires going to it on the tps and then a little short harness going off it to the 3 prong grey plug in which you'll get your 0-5v reference for throttle position.

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alexideways    12

Hi, alexidewayz again so, I'm done tagging every function to every wire in the harness and I'm puzzled by a few things.

 

1-Why are the injector grounds all clustered in a brown connector?????

 

2-I have a purple plug on my intake manifold, it contains 1 solid yellow wire that goes to ???? on the chassis (the connector was cut off) and 1 solid grey wire that goes to PIN 36 in the ECM but, when I check the pinout that I have, PIN 36 is marked as (-) or not used.

WTH?

When I check the pinout from the RB26 wich shares the same ECM plug as the RB25, PIN 36 is marked as (IAT sensor sign. I guess, from the shape of the device, this could be it. See 1st thumbnail

 

3- I have some kind of a shunt, or I don't know what that was tapped to my power transisor control signal plug and I can't find where it was plugged. See 2nd thumb nail.

 

Thanks.

2113_thumb.attach

PWR transistors + mystery shunt_thumb.jpg

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alexideways    12

One thing that's good to know for those with a series 2 harness, when you look at the ECCS relay, you'll notice that it's marked as pin 3-5 being switched voltage and 1-2 being the coil but, when you look at the diagrams, it's the other way around.

Well, to be sure, I tested the relay and determined that the diagrams are right. Strange that they made a mistake like that, at the factory.

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alexideways    12
...the thin grey wire that goes to the 8 pin skyline plug off the maf harness doesn't have the grey wire in it to feed ignition power to the fuel injectors from there. So i'm just gonna tap into it at the injector goofy lookin 8 post plug cause it does have the wire there.

 

I don't think you need to do this. The thick grey wire from the "goofy lookin' " 8 prong INJ. plug you are refering to goes right to (trough 2 splices) pin 45 "main IGN. power" so, I guess that in the series 2 they powered the injectors differently than series 1.

 

Here's a link to my tread where I asked a few questions and got a few answers too.http://forums.hybridz.org/showthread.php?p=725553#post725553

 

P.S.: :icon4: please note that in the diagrams, ECCS relay is marked as PIN 3-5 being coil & 1-2 being swiched pwr, THIS IS AN ERROR, as when you look at the relay itself, it's marked as the other way around. I checked the relay with a battery and jumpers and found out that every connection is good on the diagram, exept that they mixed the PIN numbers.

2158_thumb.attach

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Chris, can you advise me where I can run this brown plug?

RBZwire027.jpg

Does it do the same thing the "T" shaped plug did on the externally reg Z car alt.?

 

Should I run one of the wires in it to switched 12v, and the other to 12v batt post on the alt?

 

I'm goofed up here with my alt hook up. Please help!

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