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alexx933

help for stock L28et swap into a 77 280z??

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Hey, this is my first post. I've been reading up on the swap for months before now and have come across some things while performing my swap that I dont have an answer for. So for the background:
 
Purchased 77 280zed in November 2012.
​Purchased a disassembled L28et from an 83 including the ECCS, harness and pretty much everything else was included in a few totes and boxes.
 
Had the new motor reassembled and picked it up as just the engine (no manifolds, water pump, hosing, etc.)
 
I pulled the N/A motor and am currently using it as a template for putting new parts onto the turbo'd motor. It currently has the water pump, both manifolds (no fuel rail), turbo, throttle body, mounts, and some sort of oil line ??adapter?? which sits underneath the oil filter and has a couple places for oil lines (forgot to get a picture). 
 
So I'm hitting a couple road blocks of things I'm uncertain of:
 
1. Among all of the parts included, the ignition harness, coil, and ignitor are missing. So can I run the NA coil/ ignitor to the turbo distributor? How would I go about that? This thread is similar but not quite enough to answer this. http://forums.hybridz.org/topic/112234-no-ignition-harness/?hl=turbo+coil&do=findComment&comment=1050714

 

 
2. What is this? attaches to the harness right next to the air flow meter. Sorry for the crappy phone pictures, all I have. post-36377-0-69649500-1367533054_thumb.jpg
post-36377-0-79419000-1367533167_thumb.jpg
post-36377-0-37850800-1367533257_thumb.jpg

3. Another what's this? Attached to the other end of the harness near the brown relay. I think it is unneeded except for the black cord going to the black box which contains a couple wires that need power.

 post-36377-0-00887700-1367533504_thumb.jpg

post-36377-0-30486700-1367533559_thumb.jpg

 

Any help would be greatly appreciated! I'd like to finish this ASAP because it's taking space up in a shop my mechanic owns, and because it'll be fun. I work pretty much until Sunday night which is when I plan on going back to do as much work as I can until 2 next Thursday. I will have more questions because everybody seems to modify the engine(fuel rail, emmissions, intake, etc) before putting it back in, and I want to know what I can take off while still leaving myself a running engine.
 

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Hey, this is my first post. I've been reading up on the swap for months before now and have come across some things while performing my swap that I dont have an answer for. So for the background:

 

Purchased 77 280zed in November 2012.

​Purchased a disassembled L28et from an 83 including the ECCS, harness and pretty much everything else was included in a few totes and boxes.

 

Had the new motor reassembled and picked it up as just the engine (no manifolds, water pump, hosing, etc.)

 

I pulled the N/A motor and am currently using it as a template for putting new parts onto the turbo'd motor. It currently has the water pump, both manifolds (no fuel rail), turbo, throttle body, mounts, and some sort of oil line ??adapter?? which sits underneath the oil filter and has a couple places for oil lines (forgot to get a picture). 

 

So I'm hitting a couple road blocks of things I'm uncertain of:

 

1. Among all of the parts included, the ignition harness, coil, and ignitor are missing. So can I run the NA coil/ ignitor to the turbo distributor? How would I go about that? This thread is similar but not quite enough to answer this. http://forums.hybridz.org/topic/112234-no-ignition-harness/?hl=turbo+coil&do=findComment&comment=1050714

I am finishing up putting the same motor in the same year car.  I believe you need a turbo coil, it is a different part number and has different working parameters.  I believe too the ignitor is fired off of the ECCS on the turbo, so you need that. That is my thread you posted here.

 

 

2. What is this? attaches to the harness right next to the air flow meter. Sorry for the crappy phone pictures, all I have. attachicon.gif20130502_130425.jpg

attachicon.gif20130502_130348.jpg

attachicon.gif20130502_130547.jpg

 

Don't know what that is, you don't need it though.  I kept the 280zxt boot from the turbo to the AFM and hacked it down some to do the same on the swap.  I cut mine to fit the afm right before the little tit that is next to the accordion flex on the boot. This makes it so the intake side of the afm is right over the A/C compressor pulley.

 

3. Another what's this? Attached to the other end of the harness near the brown relay. I think it is unneeded except for the black cord going to the black box which contains a couple wires that need power.

 attachicon.gif20130501_175306.jpg

attachicon.gif20130502_130624.jpg

You can use that box, I didn't. All you need is the brown and green wires which get connected to 12v constant ie battery+ or starter.

 

Any help would be greatly appreciated! I'd like to finish this ASAP because it's taking space up in a shop my mechanic owns, and because it'll be fun. I work pretty much until Sunday night which is when I plan on going back to do as much work as I can until 2 next Thursday. I will have more questions because everybody seems to modify the engine(fuel rail, emmissions, intake, etc) before putting it back in, and I want to know what I can take off while still leaving myself a running engine.

 

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Go to xenons30.com / reference section and download the Factory Service Manual for both of your cars: The '77 280Z and the 280ZX.  I'd suggest the '82 FSM for the engine and associated parts - I think it's a little easier to follow than the '83 FSM.  Get all - can't hurt.

 

First, if you're using the stock ECCS system, don't "leave anything off" unless you completely understand how it's going to affect how your engine runs.  You can't go in and tune that ECU to compensate.  My opinion, but if experience holds, you're probably going to be chasing a few gremlins and you may not need the gremlins thrown in by deleting components confusing things.  Get it running properly stock first, then get the info on what and when to change.

 

1. You need a coil and ignitor but not necessarily the stock items if they're unavailable to you.  Search the Forums for "GM HEI module" - it's a ~$30 part used on Chevettes (and Corvettes) that can be wired in place of the stock ignitor.  Simple, cheap, works well.

 

2.  That's the Vacuum Control Module (VCM) - it controls both the A.A.C Valve and the EGR Valve - info in the Factory Service Manual.

 

3.  Fusable Link box from the 280ZX.  You have a couple of those near the battery of your Z - covered with white lids - 2 fusable links in each one.  Your choice to wire power to the ECCS system:  Use the 280ZX fusable links for power to the ECCS or figure out how to wire the G and Br ECCS power wires into your fusable link...  You should understand both the wiring diagram for your Z AND the 280ZX ECCS and it's interface with the body of the ZX...  Factory Service Manual.

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Thanks for the responses guys! I have tried downloading the FSM's for both vehicles before; unfortunately, I get an error that says the file can not be opened. I don't know why. I do, however, have a paperback copy of the book for a 78 that is in rough shape. Is there any way you could email/message me a copy of the unzipped files?

 

I've realized that yes the FSM is very much needed in order for me to complete the vacuum lines on the intake. The PO completely disassembled the entire intake except for the fuel rail... jerk. I might be able to run the AAC without the VCM by routing the vacuum in from a different source? 

 

Ben, will you let me know what your idle is like without the item in #2. If the AAC runs off of it, then the idle will be thrown into disarray according to some of the threads I've read. 

 

I'm just going to wire the ECCS system according to this thread http://forums.hybridz.org/topic/34469-a-quick-fi-and-ignition-280zxt-to-s30-turbo-swap-guide/.
 

As for the ignitor and coil, I just ordered a turbo coil and the GM HEI module. Wiring sounds pretty easy, and $25 is better than $155 for a brand new L28et ignitor.

 

Once again, thanks!

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I didn't use the VCM and ditched the 280zx's intake manifold altogether in favor of the manifold off of my 280z. For a fast idle, I reused the idle valve from my 280z. It needs 12 volts supplied to it when the ignition is on. As the bi-metal valve heats up, it closes the port and drops your idle. Or you can just ignore both and you might have to crack the throttle a bit to start it when it's cold, but hey it's almost summer and that's a winter problem, right?

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Download the WINRAR to unpack zipped folders from here http://ninite.com/

 

 

That should get you into the FSM.  You are going to need the FSM for the 82 trust me.  Even then its still a fun process to get spark, and injector pulse. Part of the injector pulse is tied to the FP relay so you will need to get an understanding of the wiring you are transplanting.  DO NOT HOOK 12V ANYWHERE until you know for a FACT with 100% certainty that your wiring is right. 

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Even the WINRAR can't unpack the file from xenons130. It is either corrupted or a wrong format. Thanks for the advise on the wiring. I definitely do NOT want to fry any of the wires or parts and have to replace either of those. 

I could probably use the 77 intake, but the 83 is already bolted on which is a pain the the ass. The TB was disconnected from the 83 intake and I compared it to the 77 to find out the 77 has a larger TB. I'm not sure why though. 

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So I've decided to forgo engaging the EGR. I will plug the EGR valve until I can make a plate. Tomorrow I will decide whether or not to trade intakes. I should rephrase the initial title for this thread by removing "stock." I'd like to run the stock ECCS with what is needed to make it run, nothing more. The reasoning for this is ease of install. I can chase gremlins later, but I want to get it out of the shop I'm using. Any links or suggestions would be appreciated. Thank you!

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Now that I have the GM HEI module, I can't seem to find a write up on how to wire it. The tabs for the connections are not labeled which leaves me without an idea of which wire needs to be connected where. I have found skittle's write up here: http://www.zcar.com/forum/10-70-83-tech-discussion-forum/285085-hei-ignition-control-module-swap-info-turbos-only.html. Sadly, the attachments are no longer working. 

 

Oh, and which pin number on the ECCS ends up going to the HEI?

Thanks!

Alex 

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I never attempted to use the 4pin with the stock ECCS, but I would imagine it gets wired up the same as if using Megasquirt.

 

B = Switched 12v (o-ring connector from coil (+) to spade on the HEI should do it)

C = Coil Ground

G = Signal from ECU

W = Ground

 

The HEI module grounds the coil through the casing with the mounting screws. You might want to run an extra lead off of that to make sure the module is getting a nice and solid ground.

 

Moby's MS diagram

8239mss_schematic.jpg

Edited by Metro

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Thanks Metro! that diagram definitely helps. I now have the engine entirely in and just need to begin wiring. Because I don't have the ignition harness, I was going to splice into the plug that the harness connects to. Figure Q on http://forums.hybridz.org/topic/34469-a-quick-fi-and-ignition-280zxt-to-s30-turbo-swap-guide/

is the ignition harness plug. If I splice into the wiring to extend the wires, on the EFI harness, do the same rules apply as if I cut the wires on the ignition side? I just want some confirmation before I hack my harness up. 

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On the 280ZXT, the wiring to the coil / ignitor is seperate from the engine harness, just like your '77.  It actually only has ONE wire that ties back to the ECU - the Yellow/White "signal" wire that's part of the ignitor plug.  Your '77 already has the other two wires - they went to your original coil: 

 

A Black/White that comes from the IGN switch - it's +12V at IGN ON - powers both the ignitor and the coil (+). 

The other is a Blue, for the Tach signal.

The turbo coil and ignitor get their GND from the frame & the coil/ignitor bracket being bolted to it (fender well).

 

The only wire you're really missing is the ignitor signal from the ECU.  Run a wire from the ignitor (HEI) to the correct pin on "plug 2" near the ECU and you're set - plus you've got the Tach hooked up (Blue Tach signal wire to same post (-) on the coil that the blue wire from the ignitor would connect to  (in your case, HEI...)  On "plug 2"  there are multiple yellow's, there's even a YW on either side.  The YW you're looking for is on the side with a Black, Yellow, and Yellow/White (maybe a 2nd Black) - the "wrong" side has a Green/Blue, Yellow, Yellow/White, (& maybe a Black)

 

You can use some of your existing wiring OR you can recreate the 3 wires that are the stock ignitor harness: BW +12V from the IGN ON, Blue signal to the Tach resistor, YW ignitor signal to the ECU, GND to the frame.

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So after hours of tinkering with the wiring, I still couldn't get spark. I used the black and white striped wire to the + terminal on the coil and the white and black striped to terminal B on the HEI module. Both of those wires came from the stock 77 harness (great idea cgsheen!). Hooked a wire from the negative on the coil to terminal C. Although the HEI module isn't mounted and ground through the bottom, I ground it from terminal W and used a couple clips to ground the bottom. As for the wire running to the ECCS, I ran it from terminal G to where pin 1 from figure Q on http://forums.hybridz.org/topic/34469-a-quick-fi-and-ignition-280zxt-to-s30-turbo-swap-guide/ would plug into.

 

Then I tried to start it thinking everything was good. Starter cranked and that was it. Turns out that I was getting no spark out of the coil. We were thinking that the ECCS wasn't sending out the signal through the wire I hooked it up to. We also plugged a special injector light, which turns on as if it was an injector, into the harness at the injectors. That also didn't work. The mechanic whose shop I'm partially occupying thinks there might be something wrong with the CAS because of that. It seems I have an 81 motor or harness but an 83 ECCS. The CAS is mounted down by the crank instead of in the distributor. Not sure if that would be an issue.

I can't seem to find the page with the wiring diagram including the specific ECCS pin that leads to the HEI module. The wiring seems to be the hardest part of this, and I know it shouldn't be this hard even for a newbie. 

 

Again, thank you very much! 

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Pin 5! Thanks! One more question: on the female plug that connects to that figure Q, plugs 1 and 3 would be in the opposite positions correct? That was causing some confusion as to which wire shouldbe where. Plug one would now be in the bottom right hole and 3 should be in the top left?

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So after another review of the guide, I believe I wired the relay side incorrectly. The brown and green that ran to the fusible links are on the starter. The solid green is on a constant which leaves me with 2 wires no longer hooked up: The blue with red and the black and white. The black and white is cut off before the relay and runs into the relay. This seems to be the opposite of what the guide says to do.

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So after another review of the guide, I believe I wired the relay side incorrectly. The brown and green that ran to the fusible links are on the starter. The solid green is on a constant which leaves me with 2 wires no longer hooked up: The blue with red and the black and white. The black and white is cut off before the relay and runs into the relay. This seems to be the opposite of what the guide says to do.

post-36377-0-85040900-1368725502_thumb.jpg

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Oops, the '81 is wired differently at the EFI Relay.  You need the wiring diagram from the 1981 280ZX FSM Turbo Supplement.  Then you'll understand the wiring on that relay.  On the '81 the injectors and primary power to the ECU aren't constantly powered.  So, both the Brown and Green power wires from the fusable links go to the EFI Relay and then on to the harnesses.  You have another set of wires to your relay, and you'll see no power to the injectors until IGN ON (with the '82-'83, that voltage is constant from the battery...)

 

Don't worry about the CAS for now.  Get all you other wiring straight and check it last.  Normally that isn't a part you have to worry about going bad...  It's connected to the ECCS harness, right (4-pin connector near the dist.)?

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Bumblezee wrote the guide using an 81 though? Wouldn't that mean that I should just do as he did? 

And yes, that is exactly right about the CAS. mounts on the AC bracket and has a plug with 4 pins up by the distributor. 

 

My TPS plug was cut off when I picked the harness up. So I spliced the plug off my old harness to use on the new one. I'm going to end up cutting the plug in figure Q in order to extend the wires and ?sauder? them together. I don't think you spell it that way. So currently, my harness is pretty much back off while it is being modified. Any other suggestions as to what else should be done?

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I'm about to tear my hair out with this. I just don't get what I'm doing wrong. The hei is wired correctly, and I'm still not getting any spark at all. Any body willing to come help? The mechanic I'm with doesn't have experience converting a vehicle so he doesn't know what I should do either.

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Break the system down in to pieces.  You can make the coil produce a spark by attaching a jumper wire to the negative coil and tapping it to ground with the key on if there's power to + post.  Connect a voltmeter or test light to Pin 5 and see if the ECU is producing the +/- voltage signal to the HEI module W pin.  Confirm good gorund from the wide mounting grommet on the module.  Confirm the the wires to the module have power at B and C when the key is on.  Somewhere out there is a way to check that the CAS is producing the signal to the ECU, find that and check the CAS signal.  Some are easy to confirm, some take a little ingenuity.

 

Follow the path and confirm as much as you can - CAS signal > ECU > ECU voltage pulse to Pin 5 > Pin 5 to HEI module > HEI module triggers coil > etc.  One or more of these things must not be happening.  If you're lucky, it will be an easy one to remedy.

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Getting spark! Put some starting fluid in and there was a big bang after a couple seconds. Figured the timing was off so I turned the distributor around. After that got nothing again but the blue / red wire isnt going to the fuel pump relay yet so that could be it.

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