Supra Forums banner
1 - 20 of 42 Posts
Joined
·
410 Posts
Discussion Starter · #1 · (Edited)
:ugh2:
I am successfully one of the first to build a guide telling you not to EXTEND THE HARNESS.

The Factory 1JZ-GTE harness is plenty long enough! doubt me ? i will prove it.

first of all extending harness causes some problems for one it haves to be done proffesionaly will make a chance for a mistake and shield jumpers are not simple because i do mill spec modifications on aircraft a lot can go wronge.

Also have you ever noticed how freakishly close the harness routes around those turbos cooking wires is not good.

ok so you ask how do i install the ecu in the factory spot with out cutting a single wire and extending it.

first take the whole clip intact with factory boots and all still on it.

second loosin the speedo hole and cabel using a rotozip (high speed router dremo) round out the speedo to the size of the second sheetmetal hole inside the supra body. at the rubber boot notch it so the speedo can be wrapped and exit the boot towards the passenger side.

third route the cable as if it were factory over the tranny tunnel behind the radio and back over into the glove box.

for the the rest i had to splice about 15 wires for the body connectors. i used the 1jz body connectors and spliced them into the old 7M engine connectors and that was it done no splicing 100's of wires just to extend them around the turbo and it looks great and its verry clean and easy to undo and even go back to 7m y i would never know.

sorry but i cant show pics to prove it because my user cp says "You may not post attachments"
 

·
Registered
Joined
·
1,054 Posts
I have made my friends MKiv Aristo JDM harness work without extending it. I had to lay out the harness and straighten the rubber on the wiring harness with a heat gun.
 

·
I'll nevAr go single!
Joined
·
994 Posts
Just a few notes though, I'm no professional, and I extended mine and the car started up on the first attempt, no engine light and no problems to speak of.

Also, my harness does not come close enought to either turbo to ever become and issue.


But, it would have been nice not splicing every single wire, but again, extending is no big deal and in my opinion has no real problems besides taking a lot of your time to do.
 

·
Banned
Joined
·
1,731 Posts
You dont have to extend but the body plug wires in a Soarer 1JZ into an SC300. Its plug and play otherwise.
 

·
Akai Suisei - 赤い彗星
Joined
·
10,376 Posts
I like my harness the way it is. Old news. Good for being able to find out yourself though. :]
 

·
Banned
Joined
·
1,731 Posts
Check out 1994-2000 Honda Accord 4-cylinder engine cold air intake pipes. Most are a direct fit for 1JZ's in SC300. Looks like u need one :)

Looks like the 90-93 Integra might fit the mk3 better
 

·
JZA70 448 rwhp everyday
Joined
·
2,994 Posts
i like being able to quickly acess my ECU makes it easy to wire in piggy backs ect.

~scott
 

·
I'll nevAr go single!
Joined
·
994 Posts
VJ RC51 said:
Check out 1994-2000 Honda Accord 4-cylinder engine cold air intake pipes. Most are a direct fit for 1JZ's in SC300. Looks like u need one :)

Looks like the 90-93 Integra might fit the mk3 better

Your talkin about me huh? I'm gonna go with the stock airbox when I have the money to do so.
 

·
Registered
Joined
·
5,231 Posts
I extended my harness and it only took a few hours. I didn't wanna try stretching the harness and I wanted to put in enough slack, so that I can possibly lay the ECU down on the floorboard, like on the MKIV and Lexus'.
 

·
Madd Tyte JDM yo ®
Joined
·
7,014 Posts
i like the way a lengthened harness fits like stock. i also like how when its laid out, it looks as if it were put there by toyota. this is my first 1jz swap w/ the first engine harness that i lengthed and modified about 2 years ago. im working on another one right now and its going to look better and stocker.


here is where it goes thru the firewall, after i did the ABS removal. i had to rewire the knock sensors after the harness was in the car... when i did the harness originally, people were still using RG6 for sheilded cable. then a few of us experimented w/ USB cables, as you can see here.
 
G

·
Pics of EvilEmpire's setup.

I thought I'd post a few pics of evilempire setup up in case anyone else is interested in taking this route. sorry for the quality.
-Darwin

http://s75.photobucket.com/albums/i...ESSINSPEEDOHOLE.jpg&refPage=&imgAnch=imgAnch4

http://s75.photobucket.com/albums/i...ESSNOHACKINGREQ.jpg&refPage=&imgAnch=imgAnch3

http://s75.photobucket.com/albums/i...pyofENGINEARIAL.jpg&refPage=&imgAnch=imgAnch2

First time posting pics. I hope they turned out.
Acutally, I think its the first time i've posted on this forum before. lol
 

·
Madd Tyte JDM yo ®
Joined
·
7,014 Posts
thats cool and all... but, what, in the name of Zeus' Butthole, is with that rat's nest of wiring behind the passenger headlight and by the brake booster?!
 
Joined
·
410 Posts
Discussion Starter · #19 ·
Possibly the wires just before they where pulled in. The wires behind the light bucket are some of the old 7M engine side harness wires I kept those for the oil pressure sender & the carbody connectors. The current outcome of this is 100% successful and verry clean to the extreme of better then factory.
 

·
Madd Tyte JDM yo ®
Joined
·
7,014 Posts
well, "better than factory" is subjective and not always desired. when people restore antique cars and muscle cars, they dont one-up the factory. its actually considered very desireable to duplicate the Factory "Flaws" and inherent traits of assembly line workers and procedures. this means having the harness run across the fire wall and utilizing factory routing points and all that good stuff.

the best comment i could get from someone is No comment at all... because they would look at my completed swap and not know that it i did it, not toyota. IF it looks exactly as toyota would have done it, ive done my job.

i know your swap will look nice and neat when its done, but itll be blatantly obvious to anyone that its not factory just by looking at it... at least, anyone who knows a little bit about supras.

you didnt really have to remove the oil pressure wiring from the 7m harness. the 1jz uses a low oil pressure circuit and an idiot light in the jza70. the sending unit is similar to the 7m and uses the same connector. all you have to do is repin the IG1 to send the low oil pressure circuit to the oil pressure guage on the M1 connector. pretty simple really. ill take a pic of the engine bay that im working on and you tell me if it looks like stock fuse box wiring before or after i got to it.
 
1 - 20 of 42 Posts
Top