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Gleason320
01-07-2009, 12:56 AM
Hey wondering if anyone known what I should do?? Almost have my ST 185 swapped into my 93 celica gts. The JDM wiring harness looks like it is going to be way too short. Can anyone help??

Ryan
01-07-2009, 01:15 AM
If I am not mistaken, in order to do the swap, you need to extend the harness in order for it to work.

Murgatroy
01-07-2009, 01:15 AM
Extend the harness.

The JDM harness is set to go in on the left side, since the JDM car was RHD, since your car is LHD you need to extend it to go in on the right side.

We have sticky in the Forced Induction Forum that cover this.

Ryan
01-07-2009, 01:22 AM
I think this is the right one.

http://www.celicatech.com/forums/showthread.php?t=6359

joe's gt
01-07-2009, 03:28 AM
extend the harness. you will be masterful at soldering by the time you are done. I have heard of people cutting a hole in the firewall somewhere as well.

I soldered and heat shrunk and my wiring has held up fine on my swap. The only thing that has held up as a matter of fact.

geebes
01-07-2009, 03:55 AM
I was going to say, why don't people just make a hole in the firewall for it?

Carolina91GT-S
01-07-2009, 04:03 AM
I guess you could make a hole in the firewall, that should work out ok too if you are into cutting up your car. It felt unnatural to me to do it. I am much more comfortable with wiring so I extended the harness. There are many methods you can use. I did it by removing the intake manifold and unlooming the whole harness so I could reroute it and have it come out of the correct side of the engine like the 5SFE does. Extended about half of the wires and shortened the other half this way. Then I reloomed it all. It worked out very well and looks a lot better than just making the harness longer and having to route it behind the engine.

Hey I was wondering though if you can tell me whether or not the stock 3SGTE right hand drive harness at least goes all the way into the cabin. I know that it is too short but if all of the connectors can at least get inside the cabin then you might be able to make an extension harness and have the connectors be protected from the environment...rather than cutting and extending the existing harness.

I think I could make a plug and play harness so people wouldn't have to cut a single wire. The real questions are:

1. Can the existing harness fit into the cabin? so the connections would be safe from water..etc
2. Could those connectors be attached to an extension harness and still fit behind the dash? the space is pretty tight.
3. Will the single small connector make it to where it needs to go? or does it need to be extended as well?
4. Can I find the female receptacle for the 3rd 5SFE ECU plug (from the chassis)? I already have all of the 3SGTE receptacles, plugs, and pins to do this. I'll start looking for this receptacle on Saturday.

I'm not promising anything but I think it would be a fun project.

Dr Tweak
01-07-2009, 04:53 AM
Really, the whole harness does not need to be extended outright. Also, there are several changes that need to be made, to the fusebox connections and the interior plugs, in order for it to all be plug and play. When we do wiring conversions, the harness is reconfigured as described above (so that it's like the USDM harness) and the needed plugs are extended using mil-spec standards so that you never have a problem.

Let me know if you'd like your harness done professionally :)

-Doc

Gleason320
01-07-2009, 07:29 PM
Thanks for your help im going to look into cutting the firewall. Ill be sure to let you know what conclusions ive come to . Again thanks for the help

Shadowlife25
02-14-2009, 03:40 PM
Thanks for your help im going to look into cutting the firewall. Ill be sure to let you know what conclusions ive come to . Again thanks for the help

That is the absolute worst idea.

If you're serious at all about doing things the right way, extend the harness.
You're talking about chopping into a unibody at the firewall, at which point it would need further structural reinforcement to make up for it.

Some might argue that it wouldn't be a "large" hole, but it's material that needs to be there.

So how about you take the time to read through all the stickies we have here, learn all you can, ask about what you don't get or need help with, and take it from there.

It seems like you want this done quickly. That is gonna cause you a LOT of problems, because it also seems like you want to take shortcuts.

Do it once, do it right. We can help you with that.

If you are gonna take shortcuts and ignore sound advice, plan to pay alot of money for the things that will be going wrong in the near future.

ChrisD
02-17-2009, 04:54 PM
Another vote for harness extension. You will need to make it 28-32" longer. Be careful on the shielded wires - you will want to use shielded wire to extend them.

Trance4c
02-17-2009, 06:09 PM
That is the absolute worst idea.

If you're serious at all about doing things the right way, extend the harness.
You're talking about chopping into a unibody at the firewall, at which point it would need further structural reinforcement to make up for it.

Some might argue that it wouldn't be a "large" hole, but it's material that needs to be there.



I'm sorry, I disagree. The small hole necessary to put the harness through is not going to be significant amount of material to negate the reason for a firewall to be there.

This is a good idea!

It is the simpliest solution, and also keeps someone from hacking up a harness. If you don't need to cut, don't cut.

This is exceptionally true for people that might not be as knowledgable or very little experience with electrical wiring. There is nothing wrong with keeping a stock harness intact, there is no way you can take that and turn it into 'shortcuts and added money in the future'. The harness will be 100% whole the way it was from the factory.

Shadowlife25
02-17-2009, 06:24 PM
What?

All the spots where there are pass-throughs to the engine bay are double wall thickness and reinforced. Though the hole may be small, it will also be ragged and likely done with a hole-saw. It may be the worst case scenario, but at the very least it will probably rust.

Since when is removing metal from a car instead of doing some simple soldering a good idea?

If he feels that his skills are not up to snuff on soldering or he simply doesn't want to do it, he can BUY THE CORRECT HARNESS. <<< That, is the simplest solution.

KoreanJoey
02-17-2009, 07:24 PM
What?

All the spots where there are pass-throughs to the engine bay are double wall thickness and reinforced. Though the hole may be small, it will also be ragged and likely done with a hole-saw. It may be the worst case scenario, but at the very least it will probably rust.

Since when is removing metal from a car instead of doing some simple soldering a good idea?

If he feels that his skills are not up to snuff on soldering or he simply doesn't want to do it, he can BUY THE CORRECT HARNESS. <<< That, is the simplest solution.

Honestly, the firewall is insufficient to be a structural bulkhead in a celica.

Shadowlife25
02-17-2009, 07:35 PM
My other points still stand.

I do truly think that just chopping a hole in a car to access something that can be done more cleanly and without cutting, is a shortcut. (no pun intended)

Maybe it's just me though. :shrug: apparently it is.

Enjoy the swiss cheese.

joe's gt
02-18-2009, 04:11 AM
I agree that cutting hole won't have any structural ill effects, but there is also the chance of it not being done properly with improper grommets and sealing of the cabin. If not done properly, the sharp metal from cutting the hole could dig its way into wires and cause major headaches.

For me extending the harness was worth the extra few hours versus trying to fab a hole and finding the proper grommet and trying to make sure it properly seals. I also didn't have to constantly worry about whether metal might be cutting into my wires because of my improper grommet installation.

But I think either way is acceptable. For me, I just found it easier to use the pre-existing hole and grommet than to try and replicate it with my own in the firewall. I think it is really a matter of whatever you feel more comfortable with. I think the soldering experience involved with extending a harness is invaluable tho.

Lagos
02-18-2009, 05:49 AM
I have had a hole cut in my firewall for about 5yrs now. My car has not fallen apart. The notion that this effects the structure of the car is ridiculous. However I will agree that it is the "ghetto" way of doing it.


Another vote for harness extension. You will need to make it 28-32" longer. Be careful on the shielded wires - you will want to use shielded wire to extend them.

Chris, this is also not the proper way to go around this. The entire harness shouldn't be extended. Instead it should be "Flipped" so that it comes out of the passengers side of the fuel rail. Thats how the oem usdm harness is done, and you only need to extend a few sensor plugs to get this done. No shielded wire needs to be cut.

There is a good thread on this topic here:
http://www.6gc.net/forums/index.php?showtopic=64392&hl=harness

Trance4c
02-18-2009, 03:13 PM
^ Ding ding. Lagos has the correct answer.

joe's gt
02-18-2009, 10:16 PM
^ well now i feel stupid. lol.