Gauging custom made fuel injection harness interest

[pakmule87]

Hey everybody. I am considering putting some time (or rather will be for one part of this) in making some fuel injection harnesses. The first project will be a cut in replacement with plugs handling the 7 pin AFM, 3 pin throttle valve, cold start, thermotime, water temp, and fuel injectors. So far for that part I have most everything researched and some stuff to start (but still need to order the rest of my supplies). For this kit, it would be connected with 2 12 pin, and 1 4 pin Deutsch connectors. It would also include a $30 set of crimpers, instructions, and a set of plugs for you to put on your end of your car. The wiring would be changed from the number code to a color code system using the same gauge wire used on the harness from factory, and everything neatly heatshrinked in place.

The second part I am thinking of, is to make an entire harness, but the trouble with doing that is sourcing the nylon plugs and finding somewhere I can get my hands on the main harness, plus a grommet for the firewall. I am considering maybe doing the same thing as the first harness I suggested and you essentially replace all the nylon plugs on your end of the car with pretty much the same deal as with before.

Any suggestions, ideas, or price you see as reasonable that you would pay for either setup?

[pakmule87]

**Update- Should anybody be interested, just about have 1 harness done after having gotten the last of my supplies in today.

Details for now for what to expect, single wall heat shrink good for up to 257 degrees F, with a short period to 392 degrees, no boots for the EV1 connectors, but I used heatshrink to seal them, color coded wiring for all wires instead of the numbered, heatshrinked butt connectors for Cold Start to TMS connectors instead of the taped splice. The heat shrink doesn't have the same gloss finish of factory, but considering the connectors to plug it in, that isn't a big concern of cosmetic over function.

All of these plugs are approximately where they should be compared to a factory harness. At most you may see up to 1" of extra length on some plugs.

I am also looking into finding the other connectors on the harness to either try to build full harnesses for just plug and play, or just finding the terminals to be able to replace old ones for rebuilds. I do have the connectors for the main plug to the ECU and the plugs on the harness I am about finished with. Anybody who has any leads for these, please let me know since it would be greatly appreciated.

Price will be a little less for at least these first 2, since I have some materials on hand that aren't costing me right now, which so far looks to be about $325 shipped/pp for members here (will be $375 when I have to restock for future harnesses). All the wires will be correct gauge, even the 12 gauge to the Air Regulator.

If you have any questions, comments, suggestions, you can either post here, or pm me. I will also post pics up after I get it finished.

PS- I went off of a 75 280z for this harness, but since it is just the 7 pin, 3 pin, and EV1 connectors, there shouldn't be a problem with working for all the 280z models. I did double check all the shop manuals to be sure that they use the same numbering for the harnesses. If there is any variation from the shop manuals, please let me know, and also what different plugs are different as well between year models would be nice

[pakmule87]

*Double posted, sorry

Edited December 1, 2012 by pakmule87

[TomoHawk]

That sounds like a really cool offer. Personally, I noticed that the AFM connector looks kinda brittle, so that is the only thing I would want to replace, Does your stuff route from the side in the factory way? I've noticed some cars that had the harness coming from the firewall at the back of the engine, and it looked a little nicer. I thought that you either needed new wires of the right lengths or to re-wrap the wires for the new route.

Edited December 1, 2012 by TomoHawk

[pakmule87]

The wires are wrapped the same as factory. The way this harness hooks in, since it isn't a full harness because at the moment I am still working on sourcing the other connectors and I have no idea what to expect for a price right now on it, is that you cut into yours. I have the length where you cut yours around the strap at the engine bay light to allow for plenty of room to put in the ne plugs to tie it in. I hope that doesn't bum anybody out about this that may be interested

Also, I forgot that I didn't order any of the crimpers (will knock that off the cost for these first 2 til I restock for the next ones), but I will provide a link to a set since they are the open barrel style, which is the same style crimp used for ends that grab the wire that is stripped back and the insulation to be sure the wire doesn't come out. The plugs have changed slightly from the orignal plan in that instead of the 4 wire plug, there will be a 3 and a 1 plug for the 12 gauge wire since the Deustch connectors I am using go up to 16 gauge wire for the largest.

Oh and Tomohawk, where does your harness come through the firewall? Is it on the driver side underneath the master cylinders like the 75/76? Just want to be sure about any changes between year models since I wish I would have taken the one out of the 77 I had junked out (was first Z I had junked) and paid more attention to everything.

[TomoHawk]

I think my wires come out in the corner by the resistor packs

No offense, because I think you are doing a terrific thing for the EFI owners, but I would probably keep my wiring the way it is, as I have upgraded certain things, and arranged things in an attractive way, and re-wrapped sections, so I'd like to keep it the way it is. Too bad it's probably a pain to remove & install, or I'll send it over to you for study.

Edited December 1, 2012 by TomoHawk

[pakmule87]

Just wanted to check since I am trying to confuse myself .

On another note, just finished the first harness. All I have to do now is type up some instructions and find a box that I can ship it in. Hopefully tomorrow will be a good day to figure out how long it takes to make in 1 sitting, since so far I am guessing at least 6-7 hours on this first one.

And hopefully I will be able to locate the terminals for the other connectors so I can start offering rebuilds. I will also gladly accept old connectors (especially the main harness and fuel injection relay) or even full harnesses that are no good for 77-78 differences or the connectors for other rebuilds.

Here are the pics of the harness, and if you buy it, you will get the other ends of the 2 12 pin connectors (shown compared to 7 pin for size comparison), 3 pin connector, and single pin (handles the 12 gauge wire), along with the pins/sockets, complete instructions including the conversion from the numbered to colored harness. Future harnesses will include the Open Barrel Crimper used for the pins, but price will be higher to offset the cost of the tool since this is usually what may not be in every tinkerer's garage. You will have to supply the wire strippers/clippers for your end, and the work to put the connectors on, or if you would prefer to send your harness to me, I can do it for you for $35 plus return shipping on top of the harness price without the crimpers.

[Zed Head]

The alternative to the full harness would be one of FricFrac's repair kits. http://forums.hybridz.org/index.php/topic/104419-s30-and-s130-wiring-harness-repair-kits-you-need-this-if-you-have-an-l28e-or-l28et/#entry1020367

You said that you were gauging interest so it seems like a good thing to know before you get too far in to it. He is a member here and posts occasionally.

[pakmule87]

I did see his thread over here. My future purchases for connectors will be from him since I had bought these for about the same price but longer shipping.

[TomoHawk]

for me, the only thing I really only need is to replace the connector & boot on the AFM. Age and the elements did a number on that. I did the injector connectors, and similar stuff a couple winters ago.

[pakmule87]

Been looking up the terminals, and so far the price I am figuring for a full harness rebuild, since I would need the 35 pin ECU connector, the 2 fuel injection relay blocks, 6 pin block, dropping resistor blocks, and some of the other single connector blocks from the old harness, that it should be at most $600. This would replace all the wires, connector terminals, and a few changes such as grounding to the body to eliminate corrosion, and adding a single MAXI fuse block to replace the fusible link (would need to have self tapping screw to mount)

I still have to locate the wider terminal for the single blocks, a replacement single connector set for the fuse block, and a suitable firewall grommet.

[pakmule87]

Sorry for all spamming with updates, but I am figuring a final cost (minus the firewall boot) for a full rebuild from the ground up (minus the blocks, since finding ones that fit into them are next to impossible, so the old ones would need to be reused) would be about $450-475 for members here with me supplying the rest of the connectors. For a basic rebuild (just replacing terminals and the connectors using FricFrac's kit, being purchased on my end) would be about $175-200. Of course if you have your own fuel harness connectors, I would be more than willing to knock down the price accordingly.

And I would also knock off the cost for anybody who would be willing to throw in some old connectors in good usable shape so I can have a few on hand for members that may have bad connector blocks (which I would hope would be very few).

On another note, anybody know someone that does good mold work with silicone rubber so we can have some reproduction firewall boots? Tempted to try my hand at it since I have the 75 harness that was butchered for knowledge (was in rough shape on the injector connectors anyways) that I can work the boot off of.