2009 Outback XT EJ20X Swap

[l88m22vette]

I just used the USDM harness and added the AVCS wiring, but I'm almost positive a JDM engine harness would work as long as you add the ECU jumper harness, use the Japanese ECU, and re-code the immobilizer. I've read a lot about swapping intake manifolds, sensors, etc., and I don't think any of that stuff matters (especially when swapping a pre-factlift engine into a pre-facelift chassis, or vice-versa). All I did was swap to the earlier 2-wire sensors and use the matching wiring since I had to get my 2008 engine working with my 2005 vehicle. It turns out that the earlier 2-wire sensors I swapped have a shield on pin 30 and need the ground wire to be bolted to the metal part of the intake manifold, I just used a bolt on my TGV deletes; I also fought with and finally got my Innovate LC-2 working. The car runs perfectly with no CELs and is fully-functional, and I've been logging it for Ed at XRT. Edited March 13, 2018 by l88m22vette

[mtnbikeman123]

Glad you got that figured out.

 

I have been enjoying the 7500 rpm redline and the more linear power of functioning AVCS. It used to have a bump in torque at around 3-4000 rpm coming onto the cams but now its much smoother! Yay AVCS

[g0lds]

Sorry to bump an old thread but I need help. I am in the process of wrapping up this swap into my 05 OBXT. I am getting a "cam position sensor a circuit low input" trouble code but both my USDM and JDM engine are 3 wire cam position sensors and are identical. I used the JDM manifold (because TGV delete), USDM injectors and wire harness but I'm still getting the code. Any ideas? Going to try to install the USDM cam position sensor just in case the JDM is actually faulty.

[Max Capacity]

For those thinking of dong this swap, may be you want to read this, http://legacygt.com/forums/showthread.php/ej20x-swap-wont-pass-il-emissions-test-computer-freezes-rpmi-269658.html

[mtnbikeman123]

g0lds, I am not really sure what to suggest. I would certainly check that you have the exhaust cam sensors connected correctly. You could swap things left to right and see if the problem follows the sensor.

 

Yeah, I wouldn't expect the JDM ecu to pass emmissions. My plan was to swap back to the US ecu if/when I need to get it scanned for emmissions.

 

For those thinking of dong this swap, may be you want to read this, http://legacygt.com/forums/showthread.php/ej20x-swap-wont-pass-il-emissions-test-computer-freezes-rpmi-269658.html

Edited May 4, 2018 by mtnbikeman123

[g0lds]

g0lds, I am not really sure what to suggest. I would certainly check that you have the exhaust cam sensors connected correctly. You could swap things left to right and see if the problem follows the sensor.

 

Yeah, I wouldn't expect the JDM ecu to pass emmissions. My plan was to swap back to the US ecu if/when I need to get it scanned for emmissions.

 

The exhaust AVCS system is unplugged as I'm running the USDM ECU+harness. I am going to go through the factory service manual flow chart for the P0340 code. I'm thinking I may have damaged a wire when replacing the harness. I'll post back after I do some diagnoses this weekend

[g0lds]

I just wanted to follow up with this... The ground wire had broken off inside of the RH (passenger) side cam position sensor connector. It wasn't till I realized there was no resistance between the wire and the chassis ground that I inspected the wire closely and realized it was completely severed inside the connector. Anyways, I spliced the connector and pigtail from the JDM wire harness and the code was gone. The motor runs wonderfully on the USDM components.

[texy32]

Well I sourced so D20 Single AVCS Heads with Air pumps. 08 OBXT Decided not to swap the whole dash loom etc..

I swapped these heads on and it is a direct plug and play now. I know most of you don't build engines etc.. so it is a lot harder for you to do what I did.

[texy32]

I have a few of these direct swap D20/EJ207 & D20/EJ20X/Y for sale on Nasioc.

I even have the Bad arss JDM/EDM V10 JDM Bigports SAVCS No Air pump. But just intake AVCS 2.0L. Same Casting as W20 V10 08 up JDM STI 2.0L It was hard to source these!

Alot harder then the D20 heads These work perfectly in 05 06 07 LGT and OBXT.

 

And for 400 can have CC chamber to 2,5L then use can have a V10 Big port 2.5L!!! It uses the same camshafts. sensors, etc... that USDM does. But you dont have to mess with Exhaust AVCS because it is not machined out for that. Once the cc is cut the heads use the same head gaskets a w25 heads do. easy to get unlike the W20 Head Gaskets/

FYI A screaming bigport in your LGT or OBXT.

 

I am never on here much

[texy32]

around 06 in Japan they started using the same TGV's as 07 STI in USDM market. the ones with a plug on only on side.

[mtnbikeman123]

So a quick update to my ongoing saga.

 

I bought a later gen motor with the smog pumps(secondary air pump and valves) and U20 heads since I read that the U20 heads are more efficient. The smog pump will also let me pass visual smog checks in California. I also bought a twinscroll downpipe from yahoo japan via Aleado so I could use the OE twinscroll turbo VF47.

 

The result is significant. I can run much more ignition timing than on the older gen motor, driveability is muuuch smoother, and I make boost sooner than with the OBXT/LGT turbo.

 

If you look at the total timing maps from the stock ROM files, the years with the secondary air pumps and U20 heads run significantly more ignition timing that the older gen motors, which actually reinforces my personal experience!! I tried to use the aggressive timing maps with the old gen motor (before I knew about this) but ended up pulling so much timing out, the map ended up looking like the stock map for the correct old gen motor with old gen Z20 heads!

 

The new motor with U20 heads and twinscroll was definitely worth the hassle. I haven't done any pure highway driving (thanks california traffic) but I expect to gain some fuel efficiency compared to the old gen motor.

 

I am working through a couple of tuning things, I am trying to get myself to a DAM of 1.0 but I am still having some residual FBKC which has been frustrating. I think this is related to a metallic rythmic ticking sound that is new with this new engine. My last engine did not make this noise. I am thinking it might be related to my poor DAM and FBKC results. I have yet to diagnose it because it only makes the noise under medium load while driving, NOT at idle or light load while driving. I need a 4 wheel dyno so I can stick my head in the engine bay at speed......or I might drop it at a shop to have them troubleshoot.

 

I am also working at running more boost and a more aggressive wastegate preload or spring to mirror some dyno results I found HERE

 

Hopefully all this information is helpful for someone! Overall I am pretty happy with the motor and that my quest for dual AVCS, twinscroll, and smooth driveability has been successful.

 

If anyone has input on my engine noise, that would be appreciated. I cant quite tell if it is engine speed related, engine noise drowns it out at higher rpms 3k+. It is not clutch or gearbox related. Maybe it is related to wastegate arm, a solenoid somewhere, avcs actuator, timing belt. Or maybe it is just that the twinscroll engine noises are different and this is normal?? All I know is that my previous motor and single scroll setup did not make this noise.

Edited October 1, 2018 by mtnbikeman123

[Somac]

Free bump for this thread. Tons of fantastic information and I see lots of people asking about doing JDM swaps lately. This is probably the most comprehensive thread around.

 

Great to hear that you got everything running smoothly. I didn't realize there'd be such a difference between facelift and pre-facelift JDM motors.

[SAABaruu]

Bump. Very good to hear the updated U20 heads allow for more timing compared to the z20. My tuner told me to not swap the z20-ej20x because it can't take any timing. I am considering the hassle of swapping in a U20-ej20x into an older gen 05 LGT. Asides swapping cam sensors (3 pin to 2 pin), do you see it requiring any additional wiring changes?

[mondtster]

Bump. Very good to hear the updated U20 heads allow for more timing compared to the z20. My tuner told me to not swap the z20-ej20x because it can't take any timing. I am considering the hassle of swapping in a U20-ej20x into an older gen 05 LGT. Asides swapping cam sensors (3 pin to 2 pin), do you see it requiring any additional wiring changes?

 

I can’t comment on the U20 heads but I can tell you that the Z20 and EJ20Y will not tolerate much timing with the fuel we have available in the US.

 

I’ve wondered how much of that was related to the heads rather than compression ratio though. The EJ20X and 20Y are engines that were definitely designed more with fuel efficiency in mind than overall power output. This can be seen in the stock calibration files and also just by the choice of higher compression ratio.

[mtnbikeman123]

Its been a while since I looked at this stuff but I think that on an 05 with the newer motor, if you use the 2 pin sensors, it should otherwise be plug and play using the US engine harness, injectors, and intake manifold. I've been out of the motor swapping game long enough now that I will be slowly forgetting everything I did here

[SAABaruu]

Thanks for the info guys!! My LGT was previously owned by a forum member here. I'll be detailing my swap in my own thread. I almost bought a ej20x until I saw this thread and read about your experience with the u20 head. Very unique circumstances that you were able to run, tune and drive with both motors!

[texy32]

I'm the one that mentioned that the U20 heads are much better. So we know that you can buy a ej20x or ej20y. Which is DAVCS. Well the newer S-GT and Exiga turbo model engines are finally starting to show up!

They have U20 heads with SAVCS. YES INTAKE ONLY.

and are Single scroll Same as USDM Headers etc..

Manifold is same as LGT and 08 up WRX.

You literally swap manifolds with the wiring harness off USDM model and it is plug and play no re pinning, changing ECU ETC. It is the easiest conversion I have done to date. If you use the yellow 565cc you don't even have to change any values in the ECU.

 

Here is one for reference. I paid $1600 for mine. Well worth the ease and hassle free install!

 

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F312344486512

 

Trying to share my useless Subaru knowledge with the community! Hope it help someone out!

[mtnbikeman123]

Thanks for the info texy, sorry I forgot to mention that I got my information from you. Do you know what the power and torque ratings are from this motor, just out of curiosity?

[texy32]

It is a EJ205 but with AVCS. So not much more than a USDM WRX. The rods being the week link.

I think your swap is cooler because you have working DAVCS!

[SAABaruu]

Thanks for the info @texy32!

 

Just wondering, what is your source of information about the U20 head design? Would you say this is the best 2L head design under the W20 JDM STI heads?

 

@mtnbikeman123 and @texy32, your information alone has helped me get the better engine and hopefully some great results. I anticipate finishing my swap by the end of this week. I will be posting a build thread after that is finished on this forum.

Edited February 6, 2019 by SAABaruu

[SAABaruu]

I forgot to ask. How did you wire the exhaust avcs exactly? 4 wires per side (total of 8), that run continuously from the sensors to the ECU? Or did you tap into the main block connector for the engine harness above the turbo?

[texy32]

My source. I got my first set of SAVCS U20 heads from Outfront motorsports.

The best head with SAVCS and no Air pump is a T20N head. It is a copy of a W20 head even uses same head gasket. But no Air pumps, D20 heads are a 2.0l clone of a D25 head off of a EJ255. If you use it the Combustion chamber need to be opened up same with older Spec B

Z20 heads. But right out of the box with aur pumps is U2O heads.

[mtnbikeman123]

In my car, I didn't have any open pins in the main connector block so I added a new waterproof connector that I zip tied next to the main block. The intake cam AVCS wires are already integrated into the harness, you just need to add the exhaust AVCS wires for the solenoid and the sensor. I ran the wires to my new connector, and then continued to run the new wires from the new connector through the bulkhead next to the main harness and then to the ECU.

 

P/Ns for my order from Mouser. Deutsch connectors are expensive but worth it. You will also need a pin crimping tool if you go this route. I bought mine from Waytek Wire a while ago LINK

 

571-WM-8P qty(1)

571-WM-8S qty(1)

654-AT60-20-0122 qty(10)

654-AT62-20-0122 qty(10)

571-DTM04-08PA-EE04 qty(1)

571-DTM06-08SA qty(1)

[SAABaruu]

Thanks this helps greatly. Im having troubles specifically sourcing the actual connector for the 2 pin avcs solenoid.

 

What timing belt kit did you use for this engine?

[mondtster]

Thanks this helps greatly. Im having troubles specifically sourcing the actual connector for the 2 pin avcs solenoid.

 

What timing belt kit did you use for this engine?

 

Did your engine not come with at least a partial wire harness you could salvage the connectors from?

 

The Legacy EJ25 timing belt kit will work for the 20X/Y. In fact, most parts will interchange. But you want to be careful and use a resource to confirm parts interchange before just assuming things will work. The older JDM motors are far worse than these for finding the right stuff.