Adapting an EJ20G ECU

Headlights to tailights and everything in between.

Moderators: Helpinators, Moderators

rob
First Gear
Posts: 183
Joined: Thu Jun 26, 2003 5:44 pm
Location: Puyallup WA
Contact:

Re: Adapting an EJ20G ECU

Post by rob »

My goal is to have fabbed PCBs by next week. It may take another few days to assemble. That is the best case.

-Rob
logan9691
Second Gear
Posts: 311
Joined: Sun Jun 15, 2008 4:40 am
Location: Ellensburg, Wa
Contact:

Re: Adapting an EJ20G ECU

Post by logan9691 »

hey rob,

can you show us how to make the 20g ecu fit in the stock legacy location please :D
VF43 custom FMIC APEXI intake Invidia 3" TBE JDM Ver. 4 RA STi trans (4.44) SPT short shifter rear LSD WRX rear axels coilover suspension JDM 4-pot front brakes drilled slotted rottors Greddy EBC tuned 20G ECU sti 550cc injectors Jecs MAF walbro 255
kimokalihi
Fifth Gear
Posts: 8360
Joined: Mon Nov 06, 2006 3:41 am
Location: Tenino, WA

Re: Adapting an EJ20G ECU

Post by kimokalihi »

Zip ties is how I had to do mine. I also had to saw off the mounting bracket that came on the EJ20G ECU because it didn't allow it to fit up in there.
98 Metro Hatch Daily Driver :)
91 SS EJ20G Engine/Tranny/Diff Swap Build Thread Here
"Your testes are close to your bottom but you still play with them all the time." Jeremy Clarkson
logan9691
Second Gear
Posts: 311
Joined: Sun Jun 15, 2008 4:40 am
Location: Ellensburg, Wa
Contact:

Re: Adapting an EJ20G ECU

Post by logan9691 »

I did that, wasn't to crazy about trying to remove the ECU board, works good and is out of my way now so I can actually drive the car comfortably. :D
VF43 custom FMIC APEXI intake Invidia 3" TBE JDM Ver. 4 RA STi trans (4.44) SPT short shifter rear LSD WRX rear axels coilover suspension JDM 4-pot front brakes drilled slotted rottors Greddy EBC tuned 20G ECU sti 550cc injectors Jecs MAF walbro 255
cj91legss
Fifth Gear
Posts: 6322
Joined: Fri Jun 20, 2008 8:17 am
Location: Lakewood, Wa 98439
Contact:

Re: Adapting an EJ20G ECU

Post by cj91legss »

i don't know if this has been covered in this post or any post on here, but will the 20G board fit in the turbo ecu housing?
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
MikeyMeyagi
Second Gear
Posts: 454
Joined: Thu Nov 23, 2006 1:07 am
Location: Maine

Re: Adapting an EJ20G ECU

Post by MikeyMeyagi »

no
94 Supra Turbo 6 speed. build in progress
98 Lexus GS300, single turbo 2JZGTE swap. daily driver
93 Impreza wagon, home brewed n/a-t ken block themed winter drift missle

*sold*
94 Alpine Sport Wagon... STi conversion, rotated turbo etc
PhyrraM
Fourth Gear
Posts: 1980
Joined: Thu Aug 11, 2005 4:34 pm
Location: Lake Elsinore, CA

Re: Adapting an EJ20G ECU

Post by PhyrraM »

The EJ22T turbo ECU is a Hitachi and the Hitachi housing and not compatable with the EJ20G ECUs.

*SOME* non-turbo ECUs are JECS and close relatives of the EJ20Gs. I have not found any that are 100% compatable, but the work to make one fit should not be extensive. When I get back to my SS, it's one of the projects I have planned.
'93 Winestone SS Auto, '91 Pearl White SS.
'93 Pure White SS EJ20G slanty intercooled, SIDESWIPED! In stasis.
'94 FWD and '95 AWD Laguna Blue SVXs.
2017 Pure Red BRZ Limited w/Performance pack
kimokalihi
Fifth Gear
Posts: 8360
Joined: Mon Nov 06, 2006 3:41 am
Location: Tenino, WA

Re: Adapting an EJ20G ECU

Post by kimokalihi »

cj91legss wrote:i don't know if this has been covered in this post or any post on here, but will the 20G board fit in the turbo ecu housing?
Nope, I tried that before cutting the bracket off my EJ20G ECU.
98 Metro Hatch Daily Driver :)
91 SS EJ20G Engine/Tranny/Diff Swap Build Thread Here
"Your testes are close to your bottom but you still play with them all the time." Jeremy Clarkson
91legacyawdturbo
Second Gear
Posts: 322
Joined: Sat Mar 03, 2007 8:10 am
Location: arvada co

Re: Adapting an EJ20G ECU

Post by 91legacyawdturbo »

cj91legss wrote:
rob wrote:I have seen them on ebay, but for something like $130. It's really looks to be a small number of changes (5 + the ignition changes). You could do this in a way that would make swapping back to stock pretty easily.

-Rob
A person could just go to a junk yard and snip out the ecu connectors and grab the ecu from an N/A and make their own harnes.


I've done this and its a b^^^^



Rob do you by chance have a ej20g ecu???
91 SS, v9 ej207 twin scroll swap, Gda wrx dash swap.
2002 wrx sport wagon
rob
First Gear
Posts: 183
Joined: Thu Jun 26, 2003 5:44 pm
Location: Puyallup WA
Contact:

Re: Adapting an EJ20G ECU

Post by rob »

Indeed I do have a spare EJ20G ECU.

As for fitting the ECU, I will post pictures how I did it. Basically I used the top half of the G case and the bottom half of the 22T case.

-Rob
kimokalihi
Fifth Gear
Posts: 8360
Joined: Mon Nov 06, 2006 3:41 am
Location: Tenino, WA

Re: Adapting an EJ20G ECU

Post by kimokalihi »

Does the ECU use the body of the ECU as a grounding point?
98 Metro Hatch Daily Driver :)
91 SS EJ20G Engine/Tranny/Diff Swap Build Thread Here
"Your testes are close to your bottom but you still play with them all the time." Jeremy Clarkson
rob
First Gear
Posts: 183
Joined: Thu Jun 26, 2003 5:44 pm
Location: Puyallup WA
Contact:

Re: Adapting an EJ20G ECU

Post by rob »

Nope.
rob
First Gear
Posts: 183
Joined: Thu Jun 26, 2003 5:44 pm
Location: Puyallup WA
Contact:

Re: Adapting an EJ20G ECU

Post by rob »

Added case pictures to the first post.
prodrive
First Gear
Posts: 176
Joined: Mon Nov 16, 2009 5:49 am
Location: socal

Re: Adapting an EJ20G ECU

Post by prodrive »

any updates on IGNITION CHANGE???
rob
First Gear
Posts: 183
Joined: Thu Jun 26, 2003 5:44 pm
Location: Puyallup WA
Contact:

Re: Adapting an EJ20G ECU

Post by rob »

updated ignition section.
ScottyS
Second Gear
Posts: 355
Joined: Sat Mar 08, 2003 6:53 am
Location: Western Nevada

Re: Re: Adapting an EJ20G ECU

Post by ScottyS »

rob wrote:updated ignition section.
Very, very interesting and encouraging. I would love to swap out my 440's and vf8 for 550's and vf43 if this swap and tuning proves feasible.

Sent from my ADR6300 using Tapatalk
1991 SS build thread: http://bbs.legacycentral.org/viewtopic.php?t=40430
MikeyMeyagi
Second Gear
Posts: 454
Joined: Thu Nov 23, 2006 1:07 am
Location: Maine

Re: Adapting an EJ20G ECU

Post by MikeyMeyagi »

its very feasible. it took me less then 2 hours to add a second igniter and keep my stock coil pack. 290whp on this setup, id say its worth it.
94 Supra Turbo 6 speed. build in progress
98 Lexus GS300, single turbo 2JZGTE swap. daily driver
93 Impreza wagon, home brewed n/a-t ken block themed winter drift missle

*sold*
94 Alpine Sport Wagon... STi conversion, rotated turbo etc
wtdash
Fifth Gear
Posts: 2345
Joined: Fri May 04, 2007 4:09 pm
Location: N. ID

Re: Adapting an EJ20G ECU

Post by wtdash »

EDIT: The JECS-labeled case from a '92-'94 NA/non-turbo Legacy ECU works well w/the EJ20G's ECU board (not the '90-'91). The screws on the side match up and hold it in place like stock.



Thanks for the ignition info....and the LINK to Rob's NASIOC write-up on converting an old EJ20G coil on plug (CoP) to work with '02+ WRX ignition coils (this isn't the EJ22T Wasted Spark>>CoP).
Last edited by wtdash on Wed Jan 01, 2014 6:49 am, edited 2 times in total.
Turbo Subies:
'87 GL-10 Turbo - SOLD
'90 BJ EJ22T/DOHC & 5speed swap - SOLD
'04 FXT, Forged internals, VF39, STI TMIC, Cobb AP- SOLD
'93 Legacy SS - 5-speed, SOLD :-(
'02 WRX -SOLD
'96 BD-turbo'd-SOLD
'98 SF - NA-T
rob
First Gear
Posts: 183
Joined: Thu Jun 26, 2003 5:44 pm
Location: Puyallup WA
Contact:

Re: Adapting an EJ20G ECU

Post by rob »

I have updated the igntion section. I was asked a very basic question that I had not considered.....will the COP coils actually fit in the EJ22T heads? I have no idea :)

So option 1 of the ignition change over is on hold until this can be verified. Anybody with experience want to add their thoughts?

-Rob
Legacy777
Site Admin
Site Admin
Posts: 27884
Joined: Tue Oct 15, 2002 11:37 am
Location: Houston, Tx
Contact:

Re: Adapting an EJ20G ECU

Post by Legacy777 »

I have my doubts the WRX style COP will fit. Here's a picture I found with a quick search.

http://media.photobucket.com/image/suba ... G_1860.jpg

You might be able to get them to work, but I think you'd be better off using an off-mounted coil/ignitor combo and then run short plugs.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
dscoobydoo
Fifth Gear
Posts: 2275
Joined: Mon Mar 08, 2004 2:30 am
Location: Auburn, WA
Contact:

Re: Adapting an EJ20G ECU

Post by dscoobydoo »

If you have WRX plugs, you can always come by and test fit. ( You have to PM and call first of course)
Yes I have too many Subarus
No you can't have one
05 GD-STI
01- RS- Swapped-07 STI
00- GF
93 SS- "the original Robtune" (now in new hands)
Florin1
Fourth Gear
Posts: 1173
Joined: Thu Dec 24, 2009 1:24 am
Location: Lynnwood, Wa.

Re: Adapting an EJ20G ECU

Post by Florin1 »

Rob did you get my email/pix?
1994 Legacy Sport Sedan.
1991 Legacy Sport Sedan.
stipro
Third Gear
Posts: 698
Joined: Mon Apr 26, 2004 4:20 am
Location: Calgary, Canada

Re: Adapting an EJ20G ECU

Post by stipro »

Just checked again tonight, WRX coils will not work on our stock heads. The coil portion is too big to fit in such a tight area, also the angle inst helping anything.
1994 ABM Sport Sedan-Not stock
1990 L series/turbo-Rally project
brand
First Gear
Posts: 170
Joined: Sun Mar 01, 2009 2:52 am
Location: Denver

Re: Adapting an EJ20G ECU

Post by brand »

I have some EJ20R coils and head covers. Doesn't look like they'll fit at all to me.
91 SS with a bunch of parts waiting on the shelf
94 SS with things and such
08 STI with stuff and junk
rob
First Gear
Posts: 183
Joined: Thu Jun 26, 2003 5:44 pm
Location: Puyallup WA
Contact:

Re: Adapting an EJ20G ECU

Post by rob »

Florin did a test fit on both his EJ22T and EJ25D heads. From the pictures, it looks like it *might* be possible for them to work on the EJ22T heads, but it would depend on if they are long enough to seat on the spark plug and some sort of custom hold down bracket would have to be made.

For the EJ25D head they fit as expected.

The EJ20R/H heads should work as well, but you will have to modify the coil bodies a little bit. This is the same as the early Legacy EJ20G versions. You can tell those because they have 2 bolts instead of one holding the coil in place.
http://forums.nasioc.com/forums/showpos ... tcount=213
http://forums.nasioc.com/forums/showpos ... tcount=216

I will update the first post to reflect this info.

-Rob
Post Reply