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Discussion Starter #1
I have a 2008 Subaru forester automatic and I've been looking into getting a 2.0L EJ20Y with a manual transmission and swapping my engine because the body of the car is in nice condition and it seems to be a fun and cheap way of getting an overall better car. I was wondering what is the best way to go about it? Should I leave them together and just put them in as one whole piece or should I separate them and put them in one at a time? Also, would I need a new ECU, and what are all the extra things I would need for the transmission because I'm switching a manual. I'm sure I'm missing some stuff but if you have done it how did it turn out for you and how much would it be overall? I really need a list of stuff i would need.
 

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The most difficult part is the wiring, you should start by researching which companies make conversion subaru wiring harnesses.

Contact them and see if they'll even take on your ej20x/y into a 2008 forester swap.

Also, all are welcome on RS25, but have you also asked your swap questions on a Forester forum?
 

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'96 OBS
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some notes on those:
  • EJ20X/Y are dual AVCS, so you need to take that into account when finding a matching ECU and considering wiring
  • Stock they come with a twin-scroll turbo, which is great but make sure you take that into account when considering the overall exhaust system (might need a matching downpipe?)
  • They're 9.5:1 CR with a turbo. Depending on what kind of gas you can get in your area that could be somewhat marginal.
  • This is well into the CANBus and immobilizer era for Subaru engines and ECUs. You need to find out what you need to make that work, whether it's a matching gauge cluster, reprogramming the ECU or going to an aftermarket ECU

All that said, they keep showing up on ebay for smoking hot prices, so I definitely encourage you to find out more, do the swap and write it up so I can copy you. :D
 

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Discussion Starter #4
The most difficult part is the wiring, you should start by researching which companies make conversion subaru wiring harnesses.

Contact them and see if they'll even take on your ej20x/y into a 2008 forester swap.

Also, all are welcome on RS25, but have you also asked your swap questions on a Forester forum?
Yeah I did and didn't get much of a response worthwhile and then I saw a lot about this forum for swaps. Thanks for the help ill definitely look into it.
 

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some notes on those:
  • EJ20X/Y are dual AVCS, so you need to take that into account when finding a matching ECU and considering wiring
  • Stock they come with a twin-scroll turbo, which is great but make sure you take that into account when considering the overall exhaust system (might need a matching downpipe?)
  • They're 9.5:1 CR with a turbo. Depending on what kind of gas you can get in your area that could be somewhat marginal.
  • This is well into the CANBus and immobilizer era for Subaru engines and ECUs. You need to find out what you need to make that work, whether it's a matching gauge cluster, reprogramming the ECU or going to an aftermarket ECU

All that said, they keep showing up on ebay for smoking hot prices, so I definitely encourage you to find out more, do the swap, and write it up so I can copy you. :D
I'll let you know when I get to actually doing it I'm just doing research right now and those prices are so worth it that's the main reason I'm considering it. I knew I had to do something with the ECU but I had no clue if I had to get a new one or just tune the one I had. Also, would I just be able to buy this and a new gauge cluster?
 

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I haven't thoroughly investigated the EJ20X/Y swaps, so take all this with a grain of salt, but:
  • If I understand correctly, for ECUs that have an immobilizer they need a gauge cluster that's "paired" to them at the dealer (or factory). So it's not "replace your gauge cluster" it's "get the one out of the same car as the ECU"
  • You almost certainly will not just be able to tune your existing ECU
  • That wiring harness might have stuff you want, but you need to think of it as raw materials: connectors you need, wiring to work with. You're going to be stripping it down to individual wires and figuring out where they all need to go to keep the rest of your car happy and also run the EJ20X/Y itself.

I think you're probably underestimating this whole project by about 1 or 2 orders of magnitude. Probably the best way to figure out what might be involved is read a couple threads on people who did something similar either with your car or from an Impreza or Legacy from the same era.
 

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Discussion Starter #7
I haven't thoroughly investigated the EJ20X/Y swaps, so take all this with a grain of salt, but:
  • If I understand correctly, for ECUs that have an immobilizer they need a gauge cluster that's "paired" to them at the dealer (or factory). So it's not "replace your gauge cluster" it's "get the one out of the same car as the ECU"
  • You almost certainly will not just be able to tune your existing ECU
  • That wiring harness might have stuff you want, but you need to think of it as raw materials: connectors you need, wiring to work with. You're going to be stripping it down to individual wires and figuring out where they all need to go to keep the rest of your car happy and also run the EJ20X/Y itself.

I think you're probably underestimating this whole project by about 1 or 2 orders of magnitude. Probably the best way to figure out what might be involved is read a couple threads on people who did something similar either with your car or from an Impreza or Legacy from the same era.
Yeah, I think the same thing I'm doing so much research on how to do it and I won't be doing it for a couple of months, so I have some time but the only problem is I can't find anyone that has done it completely yet so ill just keep looking and hope someone who actually knows everything does it because right now. I have seen some do an ej20x swap but that's a completely different transmission so ill keep looking around and hopefully. From what I understand the engine itself is easy to put in it's just that wiring mainly.
 

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Keep in mind that the EJ20X and EJ20Y can both be used with a manual transmission, so don't discount someone else's swap unless they actually said they kept the automatic. I'd take a look at BL/BP (2005-2009) Legacy forums. I know some people have swapped out a broken EJ255 to a JDM EJ20X/Y, so that's definitely worth tracking down. You could then find anyone who did a BL/BP NA to EJ255 swap and kind of synthesize what's needed. Also if anyone swapped a 2008-2014 Impreza to a turbo engine that might also be relevant. Just keep reading everything you can get your hands on about any swaps that involve Subarus from that era (especially with the same engine) and you'll start to get a picture of what's involved.

You're right about bolting it in being the easy part. If I had to make up some numbers, here's where I imagine you'd spend time:
  • physically taking the old engine out and bolting the new one in: 5%
  • reading wiring diagrams, reading forums about wiring/immobilizers/CANBus/AVCS/cam triggers, planning wiring, making new wiring diagrams: 40%
  • actually doing the wiring: 30%
  • fabricating brackets, running power steering lines, messing with the AC system (if you plan to keep it), screwing around with exhaust fitment: 10%
  • random stuff that just comes up in swaps that for some reason no one thought to mention: 15%

If you've never done an engine swap before, I'd plan on the car being down several weeks to maybe a couple months depending on how AR you are about your research and prep before hand.
 

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I used ej20x heads on a ej20g shortblock in my rs. As you stated, the price for the ej20x/y is definitely the best bang for the buck motor around. I would look into using an aftermarket ecu if possible. I used a vipec to control the intake and exhaust avcs and have had good luck with it. I also used a vf-37 from an ej207 instead of the factory vf-38. I found the the vf-38 uses a strange downpipe that you really can't easily source, so if the engine in question does not include it, you may have serious difficulty finding it. Putting together all of the wiring research was the most difficult, it took me probably over a hundred hours, actually doing the wiring though took less than two days. My $.02 is that if you aren't able to use an aftermarked ecu, this swap is not really tenable...
 

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Glad to hear I'm not the only one who took forever reading wiring diagrams for a swap. :) I didn't keep track of how many hours I spent looking at wiring diagrams for my EJ204 swap, but it's probably somewhere around there. Aftermarket was also the answer I came to rather than play games with picky OEM ECUs.
 

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Discussion Starter #11
Thanks for all the help I have a decent amount of time until I do the swap so im going to be doing a lot more research and I'll let you guys know what i end up doing:)
 
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