Matthew Abate

I took a stab at it:

Made some good progress on the engine harness today. Im hoping I’ll get that done this weekend. Deleting the circuits for the voltage regulator and the throttle opener and all of the related bits freed up a fair number of terminals in the colored connectors. I contemplated consolidating them but decided against it. Better to stick with the factory positions for each wire, even though I made my own diagram and labeled everything. I also decided to hard wire the fuel pump A and B harnesses into the engine and dash harnesses rather than have so many connectors. With the increased wire gauge, AC, and extra relays under the dash I need all the space I can get. No pictures today. It just looks like piles of wire right now. Oh, by the way, @SteveJ, does that relay you posted need anything special due to the negative switching on the headlights? I read somewhere that it has a common ground on the signal circuits, which makes me think it would have to be wired differently than it may be design to be wired.

I’ve seen relays like this in some build threads for various domestic cars I’ve seen around. Could be a good way to go. At the moment I am considering putting my relays in the space where my radio used to be. I was planning to have a box there for my phone but I might be able to do both. Edit: It seems that there are many manufacturers of the NLR-132, but I think the original (and probably best quality) was made by New Era for the JDM. I see a few floating around obscure corners of the internet but nothing easy to acquire without an importer in Japan.

I have been struggling to design a relay box that could fit where I want it to go and contain everything I want in it, but this morning I had an epiphany. If I can get the relays I am adding for the lights under the dashboard I don’t have to worry about it. So here’s my question: Has anyone figured out how to squeeze four more relays under the dash without them being seen? Keep in mind I have an air conditioning evaporator under there already so I think most of the space that would be there normally is already gone. I’m wondering if it’s possible to rebuild the relay board on a sheet of ABS to fit in the original location but fit 4 more relays. I’m going to look into that. If that’s not going to work I need to find a new spot in the engine bay which I don’t like.

Very cool! Where I’ve netted out on this is as follows: I am going to punt on the decision to go electric or not until I am closer to starting the car. In the mean time I will build the provisions for an electric fan into my engine harness and if I don’t use it I’ll tuck it away.

Update: I made a major decision to scrap the electric fans. After much digging around I had three major issues that were not insurmountable but we’re hanging me up and not really worth the effort. 1. I could not find a relay module that could handle 40 amps and had a provision for 6 relays (headlights, parking lights, and fans). I found some from MSD that can hold 1, 2, or 4, and I could gang them up, but it was getting sloppy. On top of that the extra wiring was not appealing. 2. Making sure that I was pulling at least as much air as the mechanical fan was also starting to become a mess of options and getting a fan shroud that works with the various radiators I am considering, fits fans that pull enough air (>2,800 CFM total) was not impossible but was giving me a headache. 3. Buying everything necessary to do an electric fan setup is more expensive that replacing my mechanical fan (or refurbishing my old one) and having been out of work for seven months now, I can justify that. So, I am probably going to get a new fan and clutch, buy a fiberglass fan shroud from MSA, and call it a day. Now back to our regularly scheduled programming.

Looks like the electric fans MSA and Z Car Depot are selling are pulling between 10 and 25 amps. I’m going to look further but I’m speculating that 12 AWG would be sufficient if those numbers are accurate. However, if I need to go above 30 amps, the tech rep at Eaton recommended this stand alone relay/fuse power relay module they make. https://www.eaton.com/us/en-us/catalog/emobility/series-37700-pfm-prm.html

Good point. The search continues.

I haven’t decided if I’m going to get the LED headlights yet. I may go with H4s and driving lights, so I want to be able to handle that. This is mostly because I don’t want to cut the headlight cups behind the bulbs to fit the LED cooler. I am doing an electric fan so I’m going to need those 40 amps. That’s how I got on this train of thought. But I did find some 40 and 50 amp micro relays today. I’m going to see if Bosch makes any and then see what the reviews look like.

I have hit a snag. I was going to get a busman relay box with fuses to go where the voltage regulator was, but I’m realizing that between the electric fans, the headlights, and the parking lights, I would have six relays, which is going to get pretty big. The little busman box I was looking at only has room for five micro relays, but the relays in the upgrade harness are 40 amps for the headlights and I’m not seeing any micro relays that go that high. So now I am rethinking this whole strategy. I could keep the relays for the headlights and parking lights on the upgrade harnesses, but I am not sure where I will secure them and they wouldn’t be covered. I could get a bigger relay box, but I don’t know where to mount it. I suppose I could forego the fuse in the box and use a box just for relays and have inline fuses as they are in the upgrade harnesses now. What do you guys think? @SteveJ, I’m interested in your opinion on the best brands for relays as well.

Rad! Thank you. I had no idea what they were called.

Thanks. Another question… Is it possible to buy the little ends that are crimped onto the wires that go into the connectors for the dash bulbs? I’m talking about the ones that are like a split cylinder with a hemisphere on one end and make contact with the bottom of the bulb. If so, what are they called? I’m struggling to find them when I search.

One of the factory tape wraps came off a splice on my old harness and I noticed this: I don’t know if they did that from the factory or if this is a repair. I have a few other splices where the tape came off and they don’t have this clamp wrapped around the wires. I’m inclined to think it’s from the factory, though.

I’m well and truly in it now! I put the OEM color coded connector onto my new custom body harness, so I’m committed. No problems really other than putting the first terminal on upside down so the label wouldn’t have been visible. It was a pain to get off so I know my crimps are good. 😁👍🏻 Now I know not to shrink the labels until after the terminals are on the wire and properly aligned to the connector. The shrink wrap labels are what I’m really showcasing here, though. I got this trick from a guy I knew in the IT team of one of my past jobs. They would label all of their Ethernet cables like this so they didn’t have to chase wires later. These HSE label cartridges are what was holding me up. I had ordered 5.8mm, which looked really clean and tidy but is too small for this marine wire with it’s crazy thick insulation, so I had to order some 8.8mm. But it’s a breeze to put on. The only thing I would improve is making the label maker print on both sides, which is too much to ask for low end office equipment. Heres my test fit with the 8.8:

Finished the wiring part of the body harness. All of the splices are strong and I have good continuity throughout, with no more than 0.20 Ω of resistance on any given wire. All of the branch points are zip tied in the same locations as the OEM harness, so it should lay in just fine. The next step is a test fit inside the car to make sure. Separately, I was wondering if anyone knows what the blue tape Nissan used to tack down unused optional wires is. I was thinking of using blue strap tape like they use on appliances, but if there’s a way to get the real thing that would be better.

Made some major progress today! First, I was able to remove one of the colored connectors from the OEM body harness without any damage, and it looks like I should be able to source new spades for it with no trouble, so that’s a relief. Second, I finished cutting and splicing the wires for the body harness. Im not sure if you can tell, but mine is definitely beefier than the OEM harness. The overall circumference of all of the bundles together isn’t that much more, but it’s definitely weighs more. So now I need to test all of my splices with a multimeter and then put zip ties at each of the branch points. After that is heat shrink labels on each end and the colored connectors, then on to the next. Once that’s done for each harness I’ll lay them out and get the terminal connectors on, then wrap them.

I started assembling the body harness this week. I figure if the thicker insulation of the marine wire is going to be an issue it will be in the dashboard. The body harness doesn’t have to get crammed into a tight space the way the dash harnesses do, so I’m safe on this one. I’ve cut the 15 main wires that come from the two connectors at the firewall to the same length as the original wires plus an extra 14 inches to allow for putting on my connectors and any discrepancies in my measurements as I go along. For splicing I’m referring to a guide that my dad pointed me to. It’s a supplement written by Ford for for techs to work on ambient lighting in trucks and has some good diagrams for various types of splices. Here’s a PDF: 2013_truck_ambient_lighting_9-25-2012.pdf Some of the splices are a little chunky for my taste, but they’re super strong even without solder, so I’ll continue referring to it. Here’s a finished Center Splice (the first example in the guide) connecting the door switch to the wire running to the room light without cutting any wires: I’m using heat shrink on these to seal them up, but I’m also wrapping them with tape in the same colors Nissan used for referencing purposes. This particular tape came from Identi-Tape and is really nice and would probably be enough, but I have the heat shrink so I’ll use it too.

1983 280ZX with P90 head, custom 87mm domed and relieved pistons on L24 rods (9.8 compression), 45mm headers from Spirit garage in Japan (not Datsun Spirit).

New treasure! 3 Mikuni 44 PHHs. I bought these on Yahoo! Japan back in December. Jesse Streeter helped me get them Stateside and I had them rebuilt by Taka at Kyushu House, who moved to Houston in the middle of the rebuild, hence the delay. They look fantastic. The manifold also looks pretty good considering it was pretty beet up when I bought it. It had no linkage and needed to be vapor blasted, but there are very few imperfections. Just some putting on the surface that mates to the header gasket. Can’t wait to get them running.

I’m going to start with the body harness and see what the impact of the larger outer diameter looks like. If it’s overwhelming I’ll figure something else out for the dashboard. The body and engine have the room to handle it, but the dashboard may have trouble.

Here we go! Nearly 2,000 feet of wire (a surprisingly large number for such a simple and small car), connectors, tape, and the various tools that I didn’t already have for assembling the various wiring harnesses. The wire is the marine grade from Sherco Auto and Marine Supply that @SteveJ referenced at the beginning of this thread. They did a good job with the order, but I’m a little bummed about the inconsistency of the wire color, in particularly the tracer stripes. I also did not take into account the increased outer dimensions of marine grade wire. The gauge is the same, but the insulation is pretty thick. I might run into some issues when I try to lace the looms through some openings or around corners. We shall see… 🤞🏻 The connectors are the Vintage Connectors 240z kit. I will let you know how accurate it is to a 1973 setup. There will be obvious differences where the three main harnesses meet due to the lack of the colored 10-pin connectors. The tools are just Amazon specials from china. I didn’t see a need to go pro on this because I hope to never do it again. Here's the inventory of wire: Wire Gauge Wire Color Needed Link Length Price QTY Total 10 AWG Black 22 10 Gauge Black Marine Tinned Copper Primary Wire - 25 FT 25 $22.90 1 $22.90 Red w/ White 8 Primary Tracer Marine Tinned Copper 10 Gauge AWG x 25 FT Coil - Red Wire & White Striped - USA 25 $23.56 1 $23.56 White 8 10 Gauge White Marine Tinned Copper Primary Wire - 25 FTl 25 $22.90 1 $22.90 White w/ Red 20 Primary Tracer Marine Tinned Copper 10 Gauge x 25 FT Coil - White Wire & Red Stripe - USA 25 $23.56 1 $23.56 Sub-Total 58 100 4 $92.92 12 AWG Black 15 12 Gauge Black Marine Tinned Copper Primary Wire - 25 FT 25 $14.85 1 $14.85 Black w/ White 16 Primary Tracer Marine Tinned Copper 12 Gauge x 25 FT Coil - Black Wire & White Stripe - USA 25 $16.56 1 $16.56 Black w/ Yellow 22 Primary Tracer Marine Tinned Copper 12 Gauge x 25 FT Coil - Black Wire & Yellow Stripe - USA 25 $16.56 1 $16.56 Blue 4 12 Gauge Blue Marine Tinned Copper Primary Wire - 25 FT 25 $14.85 1 $14.85 Green 17 12 Gauge Green Marine Tinned Copper Primary Wire - 25 FT 25 $14.85 1 $14.85 Green w/ White 4 Primary Tracer Marine Tinned Copper 12 Gauge AWG x 25 FT Coil - Green Wire & White Striped - USA 25 $16.56 1 $16.56 Red 23 12 Gauge Red Marine Tinned Copper Primary Wire - 25 FT 25 $14.85 1 $14.85 Red w/ Black 21 Primary Tracer Marine Tinned Copper 12 Gauge AWG x 25 FT Coil - Red Wire & Black Striped - USA 25 $16.56 1 $16.56 Red w/ White X Primary Tracer Marine Tinned Copper 12 Gauge x 25 FT Coil - Red Wire & White Stripe - USA 25 $16.56 1 $16.56 Red w/ Yellow 11 Primary Tracer Marine Tinned Copper 12 Gauge x 25 FT Coil - Red Wire & Yellow Stripe - USA 25 $16.56 1 $16.56 White 5 12 Gauge White Marine Tinned Copper Primary Wire - 25 FT 25 $14.85 1 $14.85 White w/ Red 9 Primary Tracer Marine Tinned Copper 12 Gauge x 25 FT Coil - White Wire & Red Stripe - USA 25 $16.56 1 $16.56 Yellow 7 12 Gauge Yellow Marine Tinned Copper Primary Wire - 25 FT 25 $14.85 1 $14.85 Sub-Total 154 325 13 $205.02 14 AWG Black 161 14 Gauge Black Marine Tinned Copper Primary Wire - 100 FT 100 $37.71 2 $75.42 Black w/ White 42 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - Black Wire & White Stripe - USA 25 $10.44 2 $20.88 Black w/ Yellow 30 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - Black Wire & Yellow Stripe - USA 25 $10.44 2 $20.88 Blue 28 14 Gauge Blue Marine Tinned Copper Primary Wire - 25 FT 25 $9.93 2 $19.86 Blue w/ Red 56 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - Blue Wire & Red Stripe - USA 25 $9.93 3 $29.79 Blue w/ White 57 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - Blue Wire & White Stripe - USA 25 $10.44 3 $31.32 Blue w/ Yellow 10 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - Blue Wire & Yellow Stripe - USA 25 $10.44 1 $10.44 Green 112 14 Gauge Green Marine Tinned Copper Primary Wire - 100 FT 100 $37.71 1 $37.71 14 Gauge Green Marine Tinned Copper Primary Wire - 25 FT 25 $9.93 1 $9.93 Green w/ Black 57 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - Green Wire & Black Stripe - USA 25 $10.44 3 $31.32 Green w/ Blue 21 Primary Tracer Marine Tinned Copper 14 Gauge AWG x 25 FT Coil - Green Wire & Blue Striped - USA 25 $10.44 1 $10.44 Green w/ Red 52 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - Green Wire & Red Stripe - USA 25 $10.44 3 $31.32 Green w/ White 65 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - Green Wire & White Stripe - USA 25 $10.44 3 $31.32 Green w/ Yellow 15 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - Green Wire & Yellow Stripe - USA 25 $10.44 1 $10.44 Red 32 14 Gauge Red Marine Tinned Copper Primary Wire - 25 FT 25 $9.93 2 $19.86 Red w/ Black 54 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - Red Wire & Black Stripe - USA 25 $10.44 3 $31.32 Red w/ Blue 90 Primary Tracer Marine Tinned Copper 14 Gauge x 100 FT Spool - Red Wire & Blue Stripe - USA 100 $37.58 1 $37.58 Red w/ Green 2 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - Red Wire & Green Stripe - USA 25 $10.44 1 $10.44 Red w/ White 3 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - Red Wire & White Stripe - USA 25 $10.44 1 $10.44 Red w/ Yellow 8 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - Red Wire & Yellow Stripe - USA 25 $10.44 1 $10.44 White 36 14 Gauge White Marine Tinned Copper Primary Wire - 25 FT 25 $9.93 2 $19.86 White w/ Black 66 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - White Wire & Black Stripe - USA 25 $10.44 3 $31.32 White w/ Red 4 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - White Wire & Red Stripe - USA 25 $10.44 1 $10.44 Yellow 35 14 Gauge Yellow Marine Tinned Copper Primary Wire - 25 FT 25 $9.93 2 $19.86 Yellow w/ Black 17 Primary Tracer Marine Tinned Copper 14 Gauge AWG x 25 FT Coil - Yellow Wire & Black Striped - USA 25 $10.44 1 $10.44 Yellow w/ Blue 28 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - Yellow Wire & Blue Stripe - USA 25 $10.44 2 $20.88 Yellow w/ White 17 Primary Tracer Marine Tinned Copper 14 Gauge x 25 FT Coil - Yellow Wire & White Stripe - USA 25 $10.44 1 $10.44 Sub-Total 1098 900 49 $614.39 Total 1325 66 $912.33

After a long hiatus due to the layoff apocalypse in the tech industry I’m back on this. I just purchase the 240z kit from Vintage Connections. It’s not exactly right for a ‘73 240z but it’s close and I can probably use the extra bits for my electric fans and the like. I’m going to have to reuse my colored connectors that join the harnesses to each other, since those are NLA. As for the wire itself, I’m going to take @SteveJ’s advice and go with the marine-grade striped wire from Sherco. It’s a step up from the standard automotive wire I had been looking at, plus I can stick to the factory wire color combinations. I’m mostly done with the modifications to my wiring diagram, with the exception of the changes to the tail lights I mentioned previously and the third brake light, as well as the 12-volt socket to replace the cigar lighter and the USB-C plugs I want to add. Should be simple. Oh, and I realized that I had been making the volt meter modification too complicated. If I retain the ammeter wiring and splice in a thin wire for the volt meter I’ll have the perfect setup for a kill switch. I will I se that switch to join the white and white / red wires (rather than splicing them) and relocate all of that down to the lower part of the dash or center console to mount the switch. Easy Peezy, in theory.

I can’t because I bought it from Z Car Depot.

Finished drawing up the wiring change for the tail lights:

Thanks for the tips @billgtp! I will file this away for later. Right now I am working on switching out the 240z turn signal switch in my diagram for one from a 260z. This mod will also involve changing the rail lights to the euro configuration. Here's the main guide I am looking at. I will be doing the same thing as the guide I am using for reference by creating an interim harness that adapts the 260z switch to the 240z dash harness. My first issue is that I made a few errors in my first diagram where I had the front turn signals going to the pin for the rear signals, and vice versa. That has been fixed. My second issue is that the tail lights all ground to the fuel tank sending unit. I need to go back to the harnesses and make sure that is correct. A quick look at the FSM tells me it is, but I am not 100% certain, given the number of other errors I found in that thing. As noted in the guide above, the 260z does not send the brake signal through the turn signal switch, so I have to figure out how that is supposed to be wired in those cars. The rest of it seems pretty straight forward, though. Here's a diagram of the two switches: In the 240z, #9 is the signal coming from the brake switch. In the 260z, the #9 is in neither the combo switch (wiper switch) nor the TS switch, so I am looking at where it goes. #10 through #14 are consolidated in the 260z. Another thing I noticed is that the tail light harnesses I got from Z Car Depot each has a socket for a dual-filament bulb where the red wire is cut and knotted. These are brand new, so I need to look into what that is for. Once I find my old ones I should be able to make a comparison and see what is up. Its a little bit of a pain because the wires switch colors underneath the wrap and have no relationship to the FSM. Fun times. *** I know it seems like I am jumping around, but I'm finding that these different sections impact each other in that I have to route wires for the new components through the colored connectors at the bulkhead, so I think it is better that I resolve all of the swaps before I resolve the additions.