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so really, how complicated is it to wire an ej swap???


doobieryan
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ive been wanting to do an ej22 swap for a while now because im gonna want more power when i lift my wagon and put the big tires i have for it on.

the thing that im worried about is when i get the ej in there im not gonna even know where to start for the wiring. are those chopped ej conversion harnesses that people on the forum sell pretty straight forward and easy to install?? please help me on this issue, i want more power and wiring makes my brain hurt!!:slobber::slobber:

thanks, Ryan

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The hard part is stripping down the donor harness. figuring out which wires to cut out, which to leave alone, and which to seperate to run to the EA body.

 

Once that is done though, it's about 6 to 8 wires to hook up.....depending on the excact configuration.

 

I think if you bought a harness stripped and labeled from Chux or other board member you would be able to do it pretty easily. The hardest part on thte install end is locating the wiring you need to tap into on the EA body........Tach, Temp Gauge, CEL, VSS, IG. 12v+, Batt 12v+, and start signal.

 

Most of that is pretty easy and members here can give you ideas ad help when you get to that stage of wiring.

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IMO (and this is just my opinion) - to do it *right* you need to get a secondary fuse panel for the power supplies to the EJ piggyback harness. Painless wireing products (summitracing.com, jegs, etc) makes some nice fuse panels with various configurations - you should budget about $100 for that and associated wireing supplies like solder and heat shrink, etc.

 

The rest of the tie-ins are relativley straightforward if you are swapping into an '82+ EA series. It's just a matter of knowing where to find the wire you need to tie into.

 

Making it run is not so hard - doing a fused, correct, labeled, and mapped wiring install is harder. Most of the swaps out there are running with a fistfull of crimp connectors, no labeling, and no way for anyone but the guy that installed it to know what the hell is going on. This is a big drawback IMO - for one thing when something goes wrong (and it's more likely to happen to the dude with the fistfull of butt-connectors and wireing extensions all made from the same color wire :rolleyes:) it's going to be a nightmare to figure it out.

 

I'm not saying you shouldn't do it - I'm saying get some practice at soldering, buy a label maker for $40 so you can make decent wireing tags, read up on wireing practices, and find out how other people have done this sort of thing. Personally I wouldn't want ANYONE to strip a harness for me - that's part of learning how the harness works and plays directly into the install process IMO. If you don't know how it works - you are going to be pulling your hair out when it doesn't run and you don't know why.

 

There's a right way and a wrong way. I'm merely advocating the right way - be it you or someone else that does it - just don't do a hack job on the wiring as you will regret it later. Especially on a wheeler.

 

GD

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IMO (and this is just my opinion) - to do it *right* you need to get a secondary fuse panel for the power supplies to the EJ piggyback harness. Painless wireing products (summitracing.com, jegs, etc) makes some nice fuse panels with various configurations - you should budget about $100 for that and associated wireing supplies like solder and heat shrink, etc.

 

I disagree. There is only a need to add one Fused, battery direct 12v supply to the EJ harness...for the main relay power. Easy to do very clean with a nice single fuse holder. Other than that, the ignition switched voltage can come from existing circuits designed to run the choke, anti diesel and ECM (feedback carbs)

 

 

The rest of the tie-ins are relativley straightforward if you are swapping into an '82+ EA series. It's just a matter of knowing where to find the wire you need to tie into.

 

Agreed

 

Making it run is not so hard - doing a fused, correct, labeled, and mapped wiring install is harder. Most of the swaps out there are running with a fistfull of crimp connectors, no labeling, and no way for anyone but the guy that installed it to know what the hell is going on. This is a big drawback IMO - for one thing when something goes wrong (and it's more likely to happen to the dude with the fistfull of butt-connectors and wireing extensions all made from the same color wire :rolleyes:) it's going to be a nightmare to figure it out.

 

Correct again, must be soldered, and it's good to use matching wire colors to existing for clarity later. I am not so sure however that it all needs to be labeled. Other than a label that shows what the donor Harness is from. This gives reference to the correct wiring diagrahms and that is the best labeling that you can have, a complete wiring diagrham.

 

Point being, having FSM diagrahm for the EA car and the EJ harness is almost essential for any install. And if you have those things, you don't need to go all out labeling.

 

I'm not saying you shouldn't do it - I'm saying get some practice at soldering, buy a label maker for $40 so you can make decent wireing tags, read up on wireing practices, and find out how other people have done this sort of thing. Personally I wouldn't want ANYONE to strip a harness for me - that's part of learning how the harness works and plays directly into the install process IMO. If you don't know how it works - you are going to be pulling your hair out when it doesn't run and you don't know why.

 

Espescially don't need to spend $40 on a label maker. Use that money to buy new plugs and wires for your EJ engine.

 

As for paying someone to strip a harness, I think if paying someone for that step of the process will make the swap happen.....whereas it otherwise is too intimidating,...... which wiring is to many,.......it's very worth it.

 

And in that case, he would get a well labeled, clean to install product and some instruction, resulting in a better job for a first timer. It would bring him closer to your "right way"

 

just don't do a hack job on the wiring as you will regret it later. Especially on a wheeler.

 

 

Agreed

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Thanks a lot everyone! Im actually pretty good at soldering because i hate crimping. With wire Crimpers the question isn't if its gonna fail, its when. :grin: When i actually start the swap i will make a thread for it so any questions i might have at the time can be answered. I had another question about the swap too, although its not related to wiring. What am i looking at for motor mounts? will i need To custom make them or does it pretty much bolt right in?

Thanks,

Ryan

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my harnesses don't use a drop of solder. in an automotive situation, I've seen age and vibration break down solder and have it crack and fail.

 

 

I use 3M perma-seal heat-shrink waterproof butt splices....for everything! They're spendy, and kind of hard to find. but worth it.

 

 

 

I've said it before. if you can follow instructions to install a set of fog lights. you can follow the instructions to install one of my swap harnesses and have it work exactly like stock.

 

 

fuse blocks are neat, but entirely unnecessary for this. in stock form, an EJ22 fuel injection system only runs through one 15amp fuse. any FI EA82 will have that very fuse in the stock fuse box that can be used. But my harnesses use a waterproof inline holder near the battery (or 2 if you want one for an integrated radiator fan control circuit). I actually did this years ago with a non-waterproof holder on my loyale, and it's still running strong (almost 70k miles now since the swap).

 

 

one of my harnesses could run (with no gauges) with only 2 splices, and bolt the ring connector to the positive battery terminal. a switched power source, and power to the fuel pump.

 

 

here's the page I send out with a stripped harness. see for yourself if it sounds do-able:

http://www.numbchuxconversions.com/Files/Harness%20info.pdf

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I disagree. There is only a need to add one Fused, battery direct 12v supply to the EJ harness...for the main relay power. Easy to do very clean with a nice single fuse holder. Other than that, the ignition switched voltage can come from existing circuits designed to run the choke, anti diesel and ECM (feedback carbs)

 

Yeah - you could reappropriate fuses from the existing panel - but invariably you need ignition switched, fuse protected circuits for *something* in a modded car - lights, stereo gear, replacing burnt stock circuits, etc, etc. And it makes a nice clean place for all that "modded" stuff to live and be labeled - I use the water resistant fuse blocks and put them under the hood. I know there are other ways, but I like to have all that stuff that's not "factory" in an accesible location and preferably all in the same location. This goes to my original point of having a clean, easy to follow and troubleshoot install. As I said it's just *my* opinion on how it should be done. I also beleive in build sheets that detail the wireing, modifications, and parts sources (brand/model/year) that replacement parts can be sourced from.

 

I'm just anal like that I guess. :)

 

As for how many fuses are required - I use the exact same fuses and fuse sizing as the stock wireing. Whatever I find when I strip the harness is how it get's hooked up. I know with the EJ swap I just did there are three fuses and with my SPFI conversions there are also three. I'm sure you could tie some of them together and eliminate fuses - but that's not how I have done it.

 

GD

Edited by GeneralDisorder
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my harnesses don't use a drop of solder. in an automotive situation, I've seen age and vibration break down solder and have it crack and fail.

 

It shouldn't if it's done with electronics grade solder and flux. If you use acid core solder or acid flux (as many people unknowingly do) it will slowely eat the metal in the wireing eventually leading to a mess where the metal becomes loose and corroded in the solder joint. That stuff is for plumbing. It has to be done right with the correct supplies.

 

The waterproof splices are ok. Most marine supply places will have a good selection of stuff like that. I occasionally will use them.

 

GD

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It shouldn't if it's done with electronics grade solder and flux. If you use acid core solder or acid flux (as many people unknowingly do) it will slowely eat the metal in the wireing eventually leading to a mess where the metal becomes loose and corroded in the solder joint. That stuff is for plumbing. It has to be done right with the correct supplies.

 

The waterproof splices are ok. Most marine supply places will have a good selection of stuff like that. I occasionally will use them.

 

GD

 

could be. I'm definitely no expert in soldering. I, admittedly, suck at it. I've seen it fail too much, and don't trust it.

 

they're not just ok. they're awesome. I get them in bulk through waytek wire, but they can be had from a number of other sources (best local source I've found is Menards. but it's still about 4x more expensive than waytek), most auto parts stores will sell you a small container of them for a couple bucks a piece.

 

 

 

 

as advertised on my website (in my sig) and elsewhere. right now a '90s EJ harness stripped to a standalone harness (for install in an old subaru, for example), is $250.

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^^AS LONG AS THE MOTOR IN YOUR DONOR IS GOOD!

 

After I pulled mine, I found the all wrong injectors, two wrong kinds, faulty iac and tps, messed with throttle body w/ screwdriver marks??, blown head gaskets, and it just goes to show, test the donors then get the good donor, fix it, THEN, strip it. I've been pulling my hair out!!!!! I'm still trying to buget this. Free at this point is too expensive! Don't give yourself the crash course in engine electronics like I did.....and others have done.( I hope I'm not the only fool like that:grin: I feel like I am).........

 

If I had only known then what I know today......:banana:

 

Well, I thought the sellers were dumb enough to not mess with things, but boy was I wrong. The trans was toast so it wasn't driveable and I'm still (toast)!. I'm about to start from scratch as it might be cheaper! We'll see.

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could be. I'm definitely no expert in soldering. I, admittedly, suck at it. I've seen it fail too much, and don't trust it.

 

they're not just ok. they're awesome. I get them in bulk through waytek wire, but they can be had from a number of other sources (best local source I've found is Menards. but it's still about 4x more expensive than waytek), most auto parts stores will sell you a small container of them for a couple bucks a piece.

 

 

 

 

as advertised on my website (in my sig) and elsewhere. right now a '90s EJ harness stripped to a standalone harness (for install in an old subaru, for example), is $250.

 

I use those waterproof shrinktube connectors in boats all the time. They work amazingly well! They can be submerged in salt water forever and nothing ever happens to them. I've never had an issue with them. As for soldering, I use high grade lead-based electronics solder and the correct flux. I make very nice solder joints, and I've never had a problem with that either. I haven't done much with car wiring yet, but TONS and TONS with boats. And on boats you see just about as adverse conditions that you see on a car.

 

As for EJ swapping, I have it in the future of my GL. Why doesn't anyone ever build the wiring harness from the engine to the computer from scratch? Is that worse than pulling a harness and stripping it?

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As for EJ swapping, I have it in the future of my GL. Why doesn't anyone ever build the wiring harness from the engine to the computer from scratch? Is that worse than pulling a harness and stripping it?

 

More expensive - and frankly if you wanted that level of quality work - it would be only marginally more expensive to go with MegaSquirt and buy one of the pre-made, printed-wire harnesses for it instead.

 

It would be expensive to source all the sheilded wire for the low-voltage sensors, and the proper deutche style connectors to go with each of the stock sending unit connectors, etc. As well as the tools to crimp those tiny terminals they use, etc. If you were going to produce a large number of harnesses because of high demand it might be worth it but the small numbers that are being done in this community are just not worth that kind of investment.

 

It's actually pretty clean to strip a harness and shorten or lengthen a few wires as neccesary to make it work as a stand alone FI/Ign. harness. You just have to know what you are doing and make the cuts and splices at appropriate points.

 

GD

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As for EJ swapping, I have it in the future of my GL. Why doesn't anyone ever build the wiring harness from the engine to the computer from scratch? Is that worse than pulling a harness and stripping it?

 

way more work. and way more expensive. and by using the stock harness, modified, not only is it cheaper and easier to do, but the stock wiring diagrams and colors are still applicable.

 

 

the down side, is you have to source a donor harness. But, I've always said it's much better to get a complete donor car....so it's just a matter of pulling it.

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ill prolly either find a wrecked lego for cheap or go to pull and save and spend about 200 bucks. well see when i get to that point. i just found a hatch for sale in town, so if i get that, then it will get the ej, not my wagon. i have big plans for a future hatch, hopefully this can be the one!!!

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I just bought a complete running and driving '93 Legacy (FWD only) for $400 bucks and drove it home. Pulled the motor and complete wiring harness in one weekend, now I'm working on removing all the un-needed wiring (head lights, horns, stereo, turn signals, air bags, and so on). I would definitely start with a whole car to get an unmolested engine and wiring harness, then you know exactly what you have.

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^^ good thoughts. I'd probably also leave the engine in the car until all the wiring is cut. Then plug the cut wiring harness into the engine to see if it runs.

Is that silly, or a good idea from those who have done it?

 

That is what I did on mine. I drove the car into the shop with the cut down harness laying on the cowl when the engine got pulled. I plugged the EJ into the GL and was driving it the next day. I would recommend this method to anyone who has the space for both vehicles.

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So does the ej mount up with no modifications other than than the conversion plate? Or do you have to make mounts for it too?

 

EA82 it will bolt right in.

 

EA81 you will need to open up(grind or torch) the holes in the crossmember a bit (1/4 inch) towards the outside.

 

Otherthan that it is totally a bolt in affair.

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