Welcome to the North American Subaru Impreza Owners Club Friday September 19, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Subaru Conversions

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 01-12-2004, 02:36 AM   #1
Kostamojen
Scooby Guru
 
Member#: 2272
Join Date: Sep 2000
Chapter/Region: BAIC
Location: haha XD
Vehicle:
2013 Subaru 599 :P
Galaxy Blue Sexy

Question Hypothetical Wiring harness question: Running an EJ20G w/ EJ18 harness

I know this might sound a little crazy to some people, but I'm trying to figure out the feasablility of running an MY98 JDM EJ20G with an EJ18 ECU and wiring harness, using only the sensors, plugs and such that I have to (IE my car does not have a knock sensor, so I wont use the knock sensor on that engine, etc.) in order to do whatever it takes to avoid swaping in a new ECU as that is not an option right now.

The engine will be in pieces, and will be rebuilt.

I guess what im trying to get at are what the essential items that are required for operating the engine, such as camshaft sensors, crank sensors, oil temp sensors, maf sensor, etc. and which ones are not. I also need to know how possible it would be to even use the wiring harness from under an EJ18 intake manifold that runs to most of the critical engine sensors and fit it onto an intake manifold compatible with the EJ20G heads. (the intake manifold can be something different, say an RS one, or a usdm WRX one, or something else perhaps that can bolt up) I also am curious about which sensors fit into which holes, IE the coolant temp sensor on the EJ18 has a different male/female plug than a newer model does, yet can the sensor be straightly swaped over?

For the sake of this discussion, Engine timing and fuel control will be controled via S-AFC and ITC. Running something more expensive (link, ecutek, whatever) is not an option. I do have access to additonal EJ18 parts as well as additional EJ20 parts if neccessary, but nothing aftermarket.

Also, will sensor values be issues with the EJ18 ECU, like camshaft/crankshaft sensor readings (BTW, they are the same sensors, but I wonder about how the ECU interprits them)

Anyway, this is all kinda ghetto, and kinda totally theoretical... But yes, I am getting an EJ20G engine this week, and I'd like to know if I will be able to use it or not, or if ill have to wait like a looooooooong long time to actually do anything with it.
* Registered users of the site do not see these ads.
Kostamojen is offline   Reply With Quote
Old 01-12-2004, 12:29 PM   #2
Zephyr
Scooby Specialist
 
Member#: 3362
Join Date: Dec 2000
Location: Central NJ
Vehicle:
2001 I've wired a
Few cars in my day

Default

If you are going to do this to your engine why don't you just save yourself some time and find a nice big dumpster and throw the whole engine in it. This is beyond half assed and I would not recomend it at all. The ECM on the two motors is compleately different. For one the EJ20 is boosted so therefore the ECM must control the boost etc. I'm sure there are even more items that will not work so I would have to say NO, DO NOT DO THIS.

Z
Zephyr is offline   Reply With Quote
Old 01-12-2004, 01:56 PM   #3
stimpy
Homicidal Maniac
Moderator
 
Member#: 1612
Join Date: Jun 2000
Location: Austin, TX
Vehicle:
2008 STI

Default

Keeping in mind that there has been atleast one person who ran the EJ22T off of an EJ18 ECU.

Conversely, though, a friend of mine is attempting to run his EJ20G off an EJ22T ECU and is failing miserably due to the large injector size differences.

-Jon
stimpy is offline   Reply With Quote
Old 01-12-2004, 05:40 PM   #4
Kostamojen
Scooby Guru
 
Member#: 2272
Join Date: Sep 2000
Chapter/Region: BAIC
Location: haha XD
Vehicle:
2013 Subaru 599 :P
Galaxy Blue Sexy

Default

The Ej20T has 360 injectors, so he must have some rather large injectors on there... I have no idea what the stock injectors are on the EJ20G, but ill find out when I pick it up.

As for being half-assed, yes it is, but I cant exactly afford anything else right now. Boost wouldnt be controled by the EJ18 ECU anyway, and the simularities between the EJ18 and EJ20 blocks are rather surprizing. The ECU is the biggest question of course, on whether it will just respond to the sensor inputs in bad fashion, but from the folks who run like EJ25's with EJ18 ECU's and most of the stock wiring there dont seem to be that many issues in that reguard, and these reasons are why I think that this might be possible to just get the engine running (it doesnt have to run at its full ability, or even run perfectly, just run without exploding which I think would be hard to do to a closed deck EJ20G anyway )
Kostamojen is offline   Reply With Quote
Old 01-12-2004, 10:50 PM   #5
Hawk296
Scooby Specialist
 
Member#: 14555
Join Date: Jan 2002
Chapter/Region: MWSOC
Location: Troy, MI
Vehicle:
1995 Impreza L
Baja

Default

you could probably get it to run in N/A form with the 1.8 ECU. you would either have to swap in EJ18 sensors or change connectors, either way no biggie.

HOwever, with it being boosted, thats a whole other animal and ide probably steer clear of it. Your ECU has no way of reading boost, thats a problem. Also it doesnt have any form of knock sensing. You could get an aftermarket knock sensing/ignition controller, and it might work. There is still no MAP sensor or anything like that, and I would NOT rely on an SAFC.

The 1.8 ECU just isnt cool enough to control a boosted motor in my opinion. You could add some of those piggyback controllers but in all seriousness your asking for trouble.

Although it is a closed deck design, the block might hold up to high boost spikes or detonation, but the pistons wont. im also really worried about the thing going lean on you and burning up your nice new engine.

Get then engine, rebuild it and save your money, get deals when you can and start planning the rest of the project. by the time you ahve the money and the rest of the parts you'll have a solid plan and be ready to tackle the swap. either if your goign WRX ECU or aftermarket standalone, I thinkit will be better than trying to cobble together something like that.

(2.0 is bigger than 1.8 and I am fairly confident you could run it in N/A form with your 1.8 exhaust off the stock ECU until you save some cash. But being lower compression I dont know if youll really make much more power than the 1.8, but then again i cant see how it wouldnt because the 1.8 is so weak. who knows it might be fun to try)

You are pretty much in the same boat i am, I dont have the cash for the rest of the parts needed for an Ej20 swap. maybe next year....
Hawk296 is offline   Reply With Quote
Old 01-12-2004, 11:53 PM   #6
Kostamojen
Scooby Guru
 
Member#: 2272
Join Date: Sep 2000
Chapter/Region: BAIC
Location: haha XD
Vehicle:
2013 Subaru 599 :P
Galaxy Blue Sexy

Default

Well the MAP sensor mod for the S-AFC reads boost. And with the ITC I can deal with timing somewhat. No, its probably not the best way to run it, but if I run it with say a TD04 at ~6-10psi at first, would it really be that big of an issue?
Kostamojen is offline   Reply With Quote
Old 01-13-2004, 12:06 AM   #7
Hawk296
Scooby Specialist
 
Member#: 14555
Join Date: Jan 2002
Chapter/Region: MWSOC
Location: Troy, MI
Vehicle:
1995 Impreza L
Baja

Default

ide still be worried and personally would not go that route, but in the end its your car. If you decide to do it that route keep us posted, it would be cool to see. good luck.
Hawk296 is offline   Reply With Quote
Old 01-13-2004, 10:59 AM   #8
Jaxx
NASIOC Supporter
 
Member#: 177
Join Date: Aug 1999
Chapter/Region: NWIC
Location: Boise,Idaho,USA
Vehicle:
The 93 Imp W/EJ20K
flat black

Default

i serously considered this exact project
i came up with a few things
#1 dohc vs sohc .. the dohc cam trigger is differnt 1 big wheel vs 2 smaller sheels (this may very well be where noah is having proublems)
#2 i would have to tweak every aspect of the timing and fuel curve (emanage) its a hack
#3 (found later) the engine is larger, will require lengtheing wires
#4 1.8 spark is too weak for forced induction and the spark plug wires will be too short
#5 no idel control unless you change the throtte bodies (1.8 is much longer intercooler wil no longer fit)

basicly no don't do it
i bought a used tec 2 kit took the harness off the 1.8 engine put it on top of the ej20 plugged in the crank,cam,temp,tps (has to be repinned), oil pressure, power steering level, coil power (to the switched power for the tec)

after i found the error in my injector harness it runs great ..
there are also several companys that sell plug and play link 2 hareness setups (sand rail guys)

are you sure that its a 98 ... pretty sure that even the 98 impreza GT was a ej205

(edit #7) ej20g injectors are 425cc almost 2x the 220cc of the 1.8

Last edited by Jaxx; 01-13-2004 at 11:08 AM.
Jaxx is offline   Reply With Quote
Old 01-13-2004, 04:18 PM   #9
Hawk296
Scooby Specialist
 
Member#: 14555
Join Date: Jan 2002
Chapter/Region: MWSOC
Location: Troy, MI
Vehicle:
1995 Impreza L
Baja

Default

Very good points. thanks for sharing.
Hawk296 is offline   Reply With Quote
Old 01-13-2004, 05:26 PM   #10
Kostamojen
Scooby Guru
 
Member#: 2272
Join Date: Sep 2000
Chapter/Region: BAIC
Location: haha XD
Vehicle:
2013 Subaru 599 :P
Galaxy Blue Sexy

Default

Quote:
Originally posted by Jaxx
i serously considered this exact project
i came up with a few things
#1 dohc vs sohc .. the dohc cam trigger is differnt 1 big wheel vs 2 smaller sheels (this may very well be where noah is having proublems)
#2 i would have to tweak every aspect of the timing and fuel curve (emanage) its a hack
#3 (found later) the engine is larger, will require lengtheing wires
#4 1.8 spark is too weak for forced induction and the spark plug wires will be too short
#5 no idel control unless you change the throtte bodies (1.8 is much longer intercooler wil no longer fit)

basicly no don't do it
i bought a used tec 2 kit took the harness off the 1.8 engine put it on top of the ej20 plugged in the crank,cam,temp,tps (has to be repinned), oil pressure, power steering level, coil power (to the switched power for the tec)

after i found the error in my injector harness it runs great ..
there are also several companys that sell plug and play link 2 hareness setups (sand rail guys)

are you sure that its a 98 ... pretty sure that even the 98 impreza GT was a ej205

(edit #7) ej20g injectors are 425cc almost 2x the 220cc of the 1.8
Excellent, good info.

For #3 i'd use the longer coil pack, and for #4 intercooler clearance isnt an issue with the air-water intercooler (its alot smaller, plenty of room to fit stuff) but ya, #1 and #2 were the problems I'm worried about...

As for the MY98, thats what I was told, but the year could be wrong but I do know that it is one of the 260ps, closed deck EJ20G engines.

Ill probably just end up using a WRX harness and ECU if I find one somewhere for cheap and when I can afford it, and deal with it like that. But that just means I wont be doing this anytime soon, and ill just stick with the EJ18 turbo im making now.
Kostamojen is offline   Reply With Quote
Old 01-14-2004, 12:08 AM   #11
Hawk296
Scooby Specialist
 
Member#: 14555
Join Date: Jan 2002
Chapter/Region: MWSOC
Location: Troy, MI
Vehicle:
1995 Impreza L
Baja

Default

Kost, we can work on the EJ20 swap planing together i mean it sounds like our cars are still gonna be identicle down the road even down to the water to air I/C!
Hawk296 is offline   Reply With Quote
Old 01-14-2004, 03:02 AM   #12
Kostamojen
Scooby Guru
 
Member#: 2272
Join Date: Sep 2000
Chapter/Region: BAIC
Location: haha XD
Vehicle:
2013 Subaru 599 :P
Galaxy Blue Sexy

Default

LOL!!! You know it was destined to be that way, our cars are nearly twins
Kostamojen is offline   Reply With Quote
Old 01-14-2004, 11:19 AM   #13
Jaxx
NASIOC Supporter
 
Member#: 177
Join Date: Aug 1999
Chapter/Region: NWIC
Location: Boise,Idaho,USA
Vehicle:
The 93 Imp W/EJ20K
flat black

Default

Quote:
4 intercooler clearance isnt an issue with the air-water intercooler (its alot smaller, plenty of room to fit stuff)
no it wont.. yeah but the pumbing won't fit right
Jaxx is offline   Reply With Quote
Old 01-15-2004, 08:48 PM   #14
Kostamojen
Scooby Guru
 
Member#: 2272
Join Date: Sep 2000
Chapter/Region: BAIC
Location: haha XD
Vehicle:
2013 Subaru 599 :P
Galaxy Blue Sexy

Default

The plumbing is quite different too, and im going to use custom plumbing anyway.
Kostamojen is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Will an '05RS (DBW) harness run an '02RS engine using the '02RS ECU? urabus555 Subaru Conversions 3 07-28-2009 09:08 AM
will an 04 sti ecu and wiring harness work on an Ej207 V8? WRXINTX Factory 2.5L Turbo Powertrain 2 02-09-2008 11:11 PM
who can wire an ej20g into a 97 OBS? evo2rex Tri-State Area Forum 3 10-09-2005 12:49 PM
Hypothetical Star Wars question: Stroke Off-Topic 58 11-17-2003 09:08 PM
Anyone Using STOCK Headunit & Sub Wiring Harness to Run a Bass Tube or Custom Sub Box clsmooth71 Bay Area Impreza Club Forum -- BAIC 4 08-27-2002 03:25 AM


All times are GMT -4. The time now is 04:45 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.