EJ20X swap?!

[CloudSeed777]

I considered this when I did my build. Doing it again I might lean this direction. Looks like a viable, cost effective alternative to #YNANSB.

[Zac88]

How did you deal with the quad cam AVCS???

[mondtster]

How did you deal with the quad cam AVCS???

 

Easy. Just use the JDM ECU that goes to the engine.

 

You'll have to add the wiring for the cam position sensors and the control valves.

 

EDIT: By the way, that's all you need to do. Or you could just run it on the original 2.5L wiring and ECU without controlling the exhaust cams.

Edited August 3, 2015 by mondtster

[Zac88]

Found these:

 

http://forums.nasioc.com/forums/showthread.php?t=2623821

http://forums.nasioc.com/forums/showthread.php?t=1941416

[mondtster]

Found these:

 

http://forums.nasioc.com/forums/showthread.php?t=2623821

http://forums.nasioc.com/forums/showthread.php?t=1941416

 

Why would you eliminate dual avcs when it isn't hard to make it work?

[Zac88]

Why would you eliminate dual avcs when it isn't hard to make it work?

 

Enlighten us then. I haven't seen a DIY on how it's done.

[mondtster]

Enlighten us then. I haven't seen a DIY on how it's done.

 

I told you what to do in my last post. Use the JDM ECU, the US wiring harness and add the wiring for the exhaust cam sensors and control valves. The biggest challenge is that the ECU is immobilized but that can be dealt with.

[Zac88]

I told you what to do in my last post. Use the JDM ECU, the US wiring harness and add the wiring for the exhaust cam sensors and control valves. The biggest challenge is that the ECU is immobilized but that can be dealt with.

 

Ok what wiring and to what pins?

 

How do you "deal" with the immobilizer? Do I need a new key? New ignition?

[mondtster]

Ok what wiring and to what pins?

 

How do you "deal" with the immobilizer? Do I need a new key? New ignition?

 

I'm not going to do everything for you, the answers to the wiring needed are readily available via the diagrams in the factory service manuals. It should just require about 8 wires to be added. Two for each cam sensor and two for each valve.

 

The dealership might be able to program the immobilizer for you, but I don't know. I pulled the key codes from the EEPROM in my US ECU and copied them to the EEPROM in my JDM ECU. Doing it this way will allow all your currently existing keys to work but I can't add a key without a trip to the dealership.

[Garmani]

Im thinking of doing the ej20x swap in my legacy gt. It is half the price of the stock ej25 and comes with a twin scroll vf38 turbo. has anyone actually conpleted the swap, fully utilizing the quad avcs?

 

Thanks,

Gabriel

[mondtster]

Im thinking of doing the ej20x swap in my legacy gt. It is half the price of the stock ej25 and comes with a twin scroll vf38 turbo. has anyone actually conpleted the swap, fully utilizing the quad avcs?

 

Thanks,

Gabriel

 

Yes, I have.

[FossMoto]

so, ive not had a computer for over a year. just used my iphone and family's PC's at their homes once in awhile. It was recently my b-day and my pops surprised me with a new laptop! very thankful and really needed this thing mine was an outdated POS. so in the past year I have bought a 2002 Impreza RS2.5 here in Wisconsin. It has a EJ251 and a 5speed in it. untouched unmolested car except for the fact it has 220k miles and the transmission sounded like metal in a blender about 5k miles after i bought it. also the engine has a what i think to be wrist pin knock.. so I pulled out the old guts and got on the internet on my phone and did a small amount of research. ended up finding a jdm legacy EJ20X on ebay for cheap with a 5speed and only 30k miles on it. the engine came with the engine bay wiring and the ecu with pigtail. I also bought a JDM forester twin turbo crossmember and had it powder coated. installed it and the engine into the impreza. sooooo now I need to get my clutch kit ordered so I can get the transmission installed. after that I'll be tackling the wiring. I have yet to pull the dash to remove the old ecu and wiring. so from the things ive read its not a easy swap and a lot of people dont want to help me out or they simply cant and are douche bags about it. I want to keep the dual avcs and plastic intake. I have deleted the air pump set-up and thats about it. I need to know a few things... i did not get a bulkhead car harness with the engine. but I found a 08+ wrx sti bulkhead harness on ebay. I was wondering if I should get it and find a usdm harness for my engine and a ecu. or should i try to find a jdm supplier that can get me a ej20x bulkhead harness from a legacy? also when splicing the harness with the 02 car harness can I make it work if the ecu is immobilized? kinda lost here and i think i picked a pretty hard swap to do. just so you people know im not a car noob. ive been swapping cars, and building stuff for years now and am pretty good at what i do. nothing is impossible i usually find a way to get things done but this is my 1st subbie swap and i need some guidance or advise in the right positive direction. guys over at Nasioc are just dickheads about it :/

[mondtster]

If you have that old of a car I'd be inclined to use an aftermarket ECU.

 

I personally wouldn't have went with a Legacy motor for this but to each their own.

[510Finn]

Easy. Just use the JDM ECU that goes to the engine.

 

You'll have to add the wiring for the cam position sensors and the control valves.

 

EDIT: By the way, that's all you need to do. Or you could just run it on the original 2.5L wiring and ECU without controlling the exhaust cams.

 

Can someone please confirm:

 

If you don't have the JDM ECU and for a 2008 LGT which is CANBUS, should be able to use the USDM ECU and not hook up the Exhaust AVCS, correct? Then just make sure to re-tune the engine.

[mondtster]

Can someone please confirm:

 

If you don't have the JDM ECU and for a 2008 LGT which is CANBUS, should be able to use the USDM ECU and not hook up the Exhaust AVCS, correct? Then just make sure to re-tune the engine.

 

You can, I drove my car for a couple of weeks on the US ECU while I was working the details out on the JDM ECU.

 

Have you looked into using an '08+ STI ECU? That might work in your application and give you dual AVCS.

[zero260]

I am looking into an outback xt manual with this motor swap and my question is, do most people do this swap with the US ECU or wire in the JDM ECU? I am wondering on how far I have to dig into it to find out how the seller had it done, I would prefer the JDM ecu. What are your opinions?

[Dusty B]

Long time no post. My searching yields some hits on my desired topic; EJ20y swap into 05 lgt. If you search my history, I did an entire drivetrain partout and went down the ls swap path. I still intend to complete, but time more than money inhibits progress and I want to just drive my car for a while again. Considering I've found multiple complete engines, with ecu, and correct trans on pallets from 1400-2300, just seems like a cost effective option in comparison to sourcing all usdm original specifics.

 

I've done my fair share of research and understand the options that come with it. Frankly, I don't see why folks wouldn't want to enable the dual avcs and reap the benefits of both twin scroll and avcs, but to each thier own.

 

I'm reviving simply to all the folks that have "dropped in" without plugging in avcs and cam sensor, what the performance was like after having a flash for the new motor? I've read other threads where guys did the drop in route, threw a gt35 on it, and couldn't figure out why they couldn't break 300hp. Believe the issue is the exhaust without being controlled default to full retarded timing and with the absence of proper valve overlap timing kills the top end. Although this certainly hurts a performance oriented turbo setup, surely this limits a relatively mild or even stock swap.

 

Also curious on why some swap intake. This may only be a requirement if going with stock single scroll setup; I know the JDM intercoolers are different. That is not really a concern of mine since I have my wbr front mount still and a lot of random ic plumbing.

 

Just looking for a little feedback.

 

Oh, and my buddy works for EFI and has confirmed they have done 2 of these as drop ins as received from an importer, flashed, and basically customers went on thier way as others have posted here. They were unable to provide me with dyno plots or customer feedback on driveability after the fact.

Edited August 10, 2016 by Dusty B

[rhino6303]

Long time no post. My searching yields some hits on my desired topic; EJ20y swap into 05 lgt. If you search my history, I did an entire drivetrain partout and went down the ls swap path. I still intend to complete, but time more than money inhibits progress and I want to just drive my car for a while again. Considering I've found multiple complete engines, with ecu, and correct trans on pallets from 1400-2300, just seems like a cost effective option in comparison to sourcing all usdm original specifics.

 

I've done my fair share of research and understand the options that come with it. Frankly, I don't see why folks wouldn't want to enable the dual avcs and reap the benefits of both twin scroll and avcs, but to each thier own.

 

I'm reviving simply to all the folks that have "dropped in" without plugging in avcs and cam sensor, what the performance was like after having a flash for the new motor? I've read other threads where guys did the drop in route, threw a gt35 on it, and couldn't figure out why they couldn't break 300hp. Believe the issue is the exhaust without being controlled default to full retarded timing and with the absence of proper valve overlap timing kills the top end. Although this certainly hurts a performance oriented turbo setup, surely this limits a relatively mild or even stock swap.

 

Also curious on why some swap intake. This may only be a requirement if going with stock single scroll setup; I know the JDM intercoolers are different. That is not really a concern of mine since I have my wbr front mount still and a lot of random ic plumbing.

 

Just looking for a little feedback.

 

Oh, and my buddy works for EFI and has confirmed they have done 2 of these as drop ins as received from an importer, flashed, and basically customers went on thier way as others have posted here. They were unable to provide me with dyno plots or customer feedback on driveability after the fact.

 

Do you have emissions testingwhere you live?

 

Will you get the harness and ecu with the engine?

 

I'd say go for it if no testing and you get the harness/ecu.

[Dusty B]

Do you have emissions testingwhere you live?

 

Will you get the harness and ecu with the engine?

 

I'd say go for it if no testing and you get the harness/ecu.

 

 

You touch on a topic i did in fact forget to include as I wrote in my tired state last night. So I have seen that the JDM ecu doesn't have all the same emissions monitors that the usdm one does. Being that the car is an 05, in ct, I believe I can have ONE monitor in not ready status and pass emissions (will validate with my friend who is emissions testing certified and owns 3 mienekes).

 

I do plan on purchasing with ecu and engine harness with intent of utilizing dual avcs once everything is said and done.

 

So, I wonder if I do what I've always done, and leave the usdm ecu in the car, with an appropriate tune, with emissions monitors ignored when I go for testing. I've passed emissions numerous times catless with open source tunes on both my now gone wrx and existing legacy. Basically I think it'd be like putting a stock exhaust on for testing like folks do, except just a matter of swapping ECU's when being tested so the testing machine sees everything it wants to. Could be a very optimistic scenario so again, just my idea on how to get around if I needed to.

Edited August 10, 2016 by Dusty B

[rhino6303]

You touch on a topic i did in fact forget to include as I wrote in my tired state last night. So I have seen that the JDM ecu doesn't have all the same emissions monitors that the usdm one does. Being that the car is an 05, in ct, I believe I can have ONE monitor in not ready status and pass emissions (will validate with my friend who is emissions testing certified and owns 3 mienekes).

 

I do plan on purchasing with ecu and engine harness with intent of utilizing dual avcs once everything is said and done.

 

So, I wonder if I do what I've always done, and leave the usdm ecu in the car, with an appropriate tune, with emissions monitors ignored when I go for testing. I've passed emissions numerous times catless with open source tunes on both my now gone wrx and existing legacy. Basically I think it'd be like putting a stock exhaust on for testing like folks do, except just a matter of swapping ECU's when being tested so the testing machine sees everything it wants to. Could be a very optimistic scenario so again, just my idea on how to get around if I needed to.

I think this would only work if the harnesses are the "same" configurations.

 

It would be super annoying to have to swap an entire engine harness and possibly bulkhead harness anytime you'd have to get emissions testing.

 

You are correct that you have to have a ton of codes turned off and ready monitors forced on. I really don't wven know if the ej20x/y will even run on a usdm ecu if you keep dual avcs and intake manifold/sensors.

[Dusty B]

I think this would only work if the harnesses are the "same" configurations.

 

It would be super annoying to have to swap an entire engine harness and possibly bulkhead harness anytime you'd have to get emissions testing.

 

You are correct that you have to have a ton of codes turned off and ready monitors forced on. I really don't wven know if the ej20x/y will even run on a usdm ecu if you keep dual avcs and intake manifold/sensors.

 

There are documented cases even in this thread, as well as in my confirmation from a very well known shop that the motor can be dropped in and operated, even without flashing for the engine (obviously rich/crappy). I think legacydan(Ireland) and mookz come to mind?

 

The only sensory differences I think are the exhaust avcs solenoids, exhaust cam sensor, and possibly a knock sensor.

 

I could be way wrong but I'm just piecing together multiple sources and what folks have done and run into. I'm totally up for debate/learning!

Edited August 10, 2016 by Dusty B

[Garmani]

Does anyone have the wiring diagram for the ej20x or subaru with this motor in it?

[mondtster]

Does anyone have the wiring diagram for the ej20x or subaru with this motor in it?

 

If you look, it is easy to find the service manual for free. Long story short, to do this swap I would suggest sticking with the US wiring harness.

[mondtster]

You are correct that you have to have a ton of codes turned off and ready monitors forced on. I really don't wven know if the ej20x/y will even run on a usdm ecu if you keep dual avcs and intake manifold/sensors.

 

It will run on a US ECU ok. I ran one that way for a few thousand miles.

 

The codes for whatever you eliminated during the swap will need to be dealt with but if you put all the US parts on it I wouldn't expect any codes to pop up when running the US ECU. There will be no control for the exhaust cams with this approach however.

[Deeregamer]

So i found a website that sells as harness that has the 8 wires to run the exhaust side avcs. it lists it as only for a 02-05 wrx and v7/8/9 jdm engine so i think this would easily bypass alot of troubles. going to call tomorrow and confirm it will work in my situation. Also just picked up a ej20y last weekend so ive been staring at diagrams for both jdm and usdm bulk harnesses for a little while trying to figure out the method to subarus madness.