Hello Everyone,

This is my first post contributing versus consuming the fantastic information I find here on NICO. I had not found any document like the one I created so after countless hours of pouring over electrical schematics, multimetering physical connections and transcribing hand-written notes to put this all together I thought I would post it for public consumption.

The document on the link below is a complete cross reference (source->destination) of all the wiring conversion/integration necessary to get a VH45DE into a Z32. Many Nissans are wired in a similar fashion so others may find this document useful as well. This document is intended to be a starting point, so any suggestions on how to improve are always greatly appreciated! Think of it as a Request for Comments (RFC) at this stage.

I am hosting this document on my servers so any changes incorporated will be placed in that document. This way we can have a "single source of truth" versus an attachment that can become outdated.

Caveat: I am waiting for craigztoys (hint-hint) as he's fabbing up my engine mounts and oilpan. With that said the wiring harness has not been tested. Craigztoys is also reviewing this document against his conversion with a 90 motor and we'll make updates as feedback becomes available. I will do the same when the motor is in my Z.

I hope you find this document useful and maybe it can save you the hours of work I put into it!

Good Luck with your projects!

Nick.

http://www.b2b-now.com/vh45det...g.pdf

Modified by npez at 4:14 PM 10/14/2008

Modified by npez at 4:15 PM 10/14/2008

Modified by npez at 11:45 PM 1/2/2009

Modified by npez at 12:32 AM 1/31/2009

You get my vote for n00b of the year... Glad to have you aboard!!!

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This site dedicated to the memory of Stacey Lynn Childs 1970-2007

Trust me guys, we have been chatting for a few weeks about this, he has a lot of time in the wiring. He did an amazing job.
Soon there will be 2 450ZX's within a hundred or so miles. i fortell awsome videos in the future.

Again, Thanx nick.

In the fsm's it lists 2 wires for the fpcu on the Z. My z only had 1. 90 na 2+2 Don't remember the color.

There are fan relay outputs from the Q ecu listed in the fsm. My 92 ecu did not have these. I believe infiniti added this feature to 94+. The early Q's have a thermoswitch in the radiators for fan activation.

Craig: Yeah I put the extra narrative at the top and notes, etc. on the bottom before posting the document as you and I have talked about this but it would be difficult for someone reading it for the first time. I fixed the typo on line C that you sent me (long nights) and will be posting the update v2.1 shortly. As for the disclaimer I had to put it in there because while the document makes it easier it's not meant to be a "how to re-wire your car for dummies" - like they say if it was easy everyone would be doing it!

T45: Thank you for the feedback. I had added a bit about the fuel pump on the normaly aspirated Zs but it's buried at the bottom under "notes" (maybe I'll bring it to the top) - I don't believe they used variable fuel pressure so they aren't equipped with that feature (it's actually shown as a whole different setup on the 11x17 wiring diagram supplement that I have). If I'm misunderstanding you let me know and I can update accordingly. As far as the Q45 is there anyway you can elaborate on the thermoswitch (wire color - basic diagram if possible and PM it to me) and I can incorporate this new information into the document (Giving you credit of course - I'm going to add a credits section to the doc).

Once again thanks to everyone.

Nick.

There are 3 wires, IIRC they are blue, green and black. Black runs to ground and I think the blue was the 190 wire. I could be wrong, it's all from memory. To find out I simply put the switch on the stove in a pot of water with a thermometer. At 190 the black made contact with the other wire, blue. I think. lol It's all taped up and a real ***** to get to for a visual.

While I am typing this (sitting in my Z in the garage) I just hooked up consult. The plug by the ECU that runs to the Z contains the consult wires. I'm not sure if you have them yet but here they are. They are as follows.

Q ecu harness to Z plug

21-brown/yellow to blue
22-yellow to white
31-brown/white to orange

I haven't tested yet, need a serial-usb for my laptop but this should be correct. I'll keep everyone posted.

Thanks Again,
Nick.

Thanks Shane. and thank you for the additional info. Let me ask you a quick (multi-part )question. On the ECM swap to pre-94, is it a plug and play affair? For example are the 94-95 EFI harnesses pinout compatible on the pre-94 ECMs? Are the 94-95 sensors compatible with what the pre-94 ECM is expecting? Are there any benefits to staying 16bit versus going to 8bit?

Since you've already done it I thought you probably have gone through the rationalization of all of this. I've got a 94 motor/95 harness and both 94 and 95 ECMs. I can go over to my friend with the junkyard and swap one of the ECMs out for a 91 or 92 that he has.

Please advise.

Thanks,
Nick.

Nick,

The harness pinouts are the same, it is a plug-n-play affair.

Also Shane,

Is there a portfolio of software/hardware tools you use that you would recommend as far as the tuning aspect of this? I'm somewhat of a noob when it comes to engine tuning though I have a general familiarity conceptually with fuel maps, timing maps, etc. and took some computer engineering classes during my undergrad work (this was ages ago though - maybe it'll come back and come in handy ).

Please advise and thanks a bunch again for your help guys....

Nick.

Components I use for tuning:

1)Tunerpro for editing the bin.

2)Burn1 hardware for burning the EPROMS. A Moates product. Flash n Burn software used for the burner.

3) ECUTalk I like for datalogs

4) Nissan Data Scan for map trace and some data logs. Also good for pulling your existing bin from an ECU.

5) Moates Ostrich 2. Don't have but I want it it is an EPROM emulator that takes place of the EPROM and allows tuning without swapping chips all the time. When used with EmUtility (free) it can allow for real time tuning. As soon as you save a bin file change EmUtility (available from the Tunerpro people) will send the new file to the Ostrich (or other emulator) even while the motor is running.

6) Nistune is also very cool but a little spendy. Allows real time tuning and map trace. These features can be done with the options above. I haven't used but it looks very cool.

7) And of course you will need a consult cable. Available from a few sources. BlaZt has one. I got mine from a NICO member, name is Jaime, can't remember his username but I'm sure I can find it. I think he also sells them on ebay. Think I paid about $70-80 IIRC.

8) Laptop

9) Wideband O2. I use the Zeitronics Zt2, I'm happy with it.

10) The chips/sockets are widely available. Moates, who sells the Burn1 and Ostrich, sells several types of sockets and chips. I like the 27SF512 which I believe is a very commonly used chip. You can write/erase/rewrite on them over and over again. I have a few of them but have been reusing the same two for dozens of tunes. While one is installed I'll make the desired changes, burn to a chip, open the ECU swap chips and do it again. This is why the Ostrich or other emulator would be awesome. Would save a ton of time.

Thanks a bunch for all the info - I'll start looking all the stuff up as far as the engine management. Most likely I'll want to go the rom emulator route for dynamic tuning

On the termo-switch is this what it looks like?

If so I guess I will need to tap into a coolant line, add a fitting and mount it (I'm using a Howe radiator which I don't believe has a port for it)? I think the wires complete the coil circuit on the relay so I should be able to recycle my rad/sub relays.

If T45's (Thanks for the info again) information is accurate then:
- Black is ground
- Blue is the ground side of the Low Speed relay coil
- Green is the ground side of the High Speed relay coil

The rest of the relay pins remain the same on the Z. Basically instead of the ECM providing ground this thermo-switch is doing the job on pre-94.

If you see yours working differently than this, please let me know.

Thanks,
Nick.

Nick.

http://store.summitracing.com/...43215

If your radiator doesn't have a threaded port for one it and you don't feel like welding a bung into one of the tanks this is another good option.

I am going to have to give the switch to my friend that's doing the supra swap, it's getting the Q45 radiator I believe. lol Gotta plug the hole back up.

1) Extra strain on the alternator since it's always running the fan when it doesn't need to.
2) Since the fuel pump comes on for 5 seconds before the engine is started so does the fan. The fan only draws less than 15 amps max so it shouldn't drain the battery. I can always pull the fuse if the battery is low and it isn't wanting to start.
3) Takes a little longer to warm up.

Works for me.

Back to topic,

I got my wiring all soldered, and wrapped, de-pinned the connectors, got them through firewall, back together, connected, everything laid out nice, while engine was in place, test fitted everything, just need to extend oil pressure wire, and splice Q alt wire into Z harness, or swap connector.

Once I went through all of it again, and again, and you know, then, made sure it will never get cut into by accident easily. I want to move some wiring more, to keep away from my unwrapped headers. The heat should not be too bad, but rather be safe, been there done that, asked How The *** did that happen? too many times.
Now that I found the right bolts, I can hopefully have it up and out this weekend. May have to take J30 to H town.

Nick.

As far as your work around, it's not perfect, but hey if it works for you and since you can live with the nuances of the workaround - I think that's great! You can still take what you have and wire in an additional relay that can be controlled by the factory 3-wire thermo-switch to get around the downsides you mentioned, but at this point that's optional since everything is working just like you have it....

Thanks again for sharing your experience with this....

Nick.

You may also want to consider this wire loom wrap in addition to wrapping your header.

http://www.jegs.com/p/Thermo+T...11801

I'm most likely going to coat the headers but will also use this for wiring along the firewall as well as wiring along the frame rails. I'm thinking replacing the plastic loom with this should work nicely....

Just a thought...

Thanks,
Nick.

An interesting thing I'm trying to sort out is the aux fans. Basically the challenge is that from the wiring diagrams it appears that the Q had 2 fans of which 1 was a 2 speed (dual windings). The Z on the other hand has 1 fan being a 2-speed on the TT. Looking further into the diagram there are some distinct differences between the Q and the Z's activation of the fans.

The Q has ECM pin 4 (thermo-switch on the pre-94s) providing relay coil ground for low speed on one fan. For high speed ECM pin 5 provides relay coil ground (thermo-switch in pre-94s) and activates the high speed winding on one fan and also activates the other fan. BTW this could be backwards as it's not indicated in the FSM which relay is high speed and which is low speed - so it could also be that one relay activates both fans on low speed and then activates the high speed winding on one fan for the second stage. The interesting thing is that in parrallel to pin 5 is the A/C pressure switch that can *also* provide ground (the other side of the switch is grounded) and activate the high speed relay.

Where it gets interesting is that on the Z the A/C pressure switch is not grounded and connectivity goes through this switch to ECM pin 9.

The simplest approach in my opinion will be to ground the other side of the Z's A/C pressure sensor to the chasis (it's by the drier in the nose) and retrofit so it works in similar fashion to the Q's setup.

I haven't updated this portion yet on the document until I try it. If it works as I expect I will document it and update the document.

Thanks,
Nick.

You will need Adobe Acrobat Reader (Free download) to open the PDF file.

http://www.b2b-now.com/vh45det...g.pdf

Thanks,
Nick.

1. Has anyone used the cranking signal wire (it is the Black/Yellow wire in the M95 connector in the foot well) when hooking their wiring up? I don't see a destination on the Q45 harness.

2. The Yellow/Blue wire that the FSM on the Z calls neutral switch; is this the clutch interlock circuit (that's what it looks like)? It seems that when the switch is closed it goes to ground. On the Q there is a Park/Neutral Position relay with a Gray wire and a Blue wire. Do one of these wires need to be grounded to signify a Neutral or Park condition? I'm trying to determine the recipient wire to integrate the clutch interlock circuit with the Park/Neutral circuit and if that's the case it makes it easy.

If anyone has any insight to this, it would be greatly appreciated.

Thanks,
Nick.

I can't recall anything about the starting signal.

The interlock wire does not need to be connected to anything at all. I believe that if grounded it will not allow engine to start so hooking up to the clutch interlock is possible, however, even with the interlock wire disconnected the car will still not start with the clutch out. The clutch safety runs through the switch on the pedal before going to the start relay so it's already wired up to work fine with the vh ecu. Easiest to just leave the interlock alone.

The wire on the drivers fenderwell that's labeled neutral actually goes to the transmission to indicate neutral to the ecu to allow the IAC to keep the revs up in between shifts on the V6. Not sure if one can incorporate it into the vh ecu or not. It sounds cooler when the rpm's drop fast to me so I did away with that wire....and the iac too!

Thanks for the feedback Ben.

Nick.

WES,

METTLER,

can we get this Sticky'd Please. There is Critical knowledge in this document that we all need at one time or another. Thanx, Craig

Capitalization is the difference between "I had to help my uncle Jack off a horse." and "I had to help my uncle jack off a horse." - unknown

Try it now though it all works.....

Thanks,
Nick.

Long time since the original message, but here is a source that is more affordable.

http://cgi.ebay.com/ebaymotors...91561

Did not connect the 5v? sensor wire to anything, no problems

did redo all the grounds, and add extras, have not had any issues.

I have not had the EGR hooked up, or the air bypass valve, although the other engine I have has the complete intake and am going to use it on the dyno to see if there is a difference between with and without EGR/airbypass. Even with it cold in the mornings, it has not been an issue, runs good from startup, great after a minute. Idle is never an issue. the connectors are just chillin there taped over.

I did put in a major modification to the engines wiring harness, that allows me to run it in 4 cyl mode, giving me about 6mpg better, and still willl easily accerate on the freeway to pass people.
I will be having this as an option on my swaps, and the harnesses I sell.
If you get a large enough aluminum radiator, and have enough air in the front, you will rarely need the cooling fans to be on.

Hope my experience helps, Craig