Engine swap EJ25 to EJ22

[doktorbill]

Thinking of swapping engines in my 98 Forester-- has a EJ25 with medium piston slap when cold, and a 5 speed trans. Have a good EJ22 in a 94 Legacy with bad auto trans. From the many posts here, looks like the EJ22 engine will bolt up once I swap over the flywheel and pilot bearing, but what about the exhaust? I can handle the intake plumbing, but I am concerned if the SOHC and DOHC heads have the same exhaust pipe bolted to them? Or am I setting myself up for some custom exhaust work? Thanks in advance for your help-- I am still a newbie on Subarus.

[Legacy777]

Exhaust ports are the same.

 

You'll run into more issues with the electronics. The first gen legacies are OBD1, your forester is ODB2.

 

There are some possible solutions, but it's not a "plug & play" type thing.

[baccaruda]

what about keeping the EJ25 manifold/wiring and just swapping longblocks (and "adjusting" the exhaust)?

[hankosolder2]

I just did an ej22>ej25 swap in my '98 Outback (thanks to the help and advice from various folks on this board!) The exhaust _should_ bolt up OK, as the '95 and earlier Legacy have dual port exhausts (two ports on each head.) The '94 Legacy engine does _not_ have an EGR port, so you will not be able to use your 2.5 EGR valve and will get a check engine light- something to bear in mind if you live in an area where they scan your car for codes during emission inspection. The best donor engine for this swap is a '95 legacy automatic- it has an EGR port and the dual exhaust port heads. The wiring harness for the '94 Legacy is incompatible with the later cars, and the 2.5 intake manifold will NOT bolt up to the 2.2. Seems like you're doing things the hard way! You might be able to use the intake manifold, engine wiring harness, sensors, throttle body, coil pack from a '95 2.2 legacy, and bolt that up to your '94 block. You'd still have the EGR issue. I can't guarantee that any of my advice will work, as I have never tried this -w- a '94 legacy block.

good luck,

Nathan

 

 

Thinking of swapping engines in my 98 Forester-- has a EJ25 with medium piston slap when cold, and a 5 speed trans. Have a good EJ22 in a 94 Legacy with bad auto trans. From the many posts here, looks like the EJ22 engine will bolt up once I swap over the flywheel and pilot bearing, but what about the exhaust? I can handle the intake plumbing, but I am concerned if the SOHC and DOHC heads have the same exhaust pipe bolted to them? Or am I setting myself up for some custom exhaust work? Thanks in advance for your help-- I am still a newbie on Subarus.

[CIS Subaru]

This is sooo strange. I just had this same idea yesterday, and was looking for an old post about it since I assumed it had been done before (given the 96-98 EJ25's reputation).

 

I also have a '98 Forester (getting oil in coolant), but I have a '97 EJ22 from an Impreza. I'm just hoping to keep the Forester driveable while I take my time with a proper EJ25 head gasket replacement. I have the Y-pipe & cats for the EJ22, so I'm not really concerned about the single-port exhaust problem. I am hoping to be able to use the Forester's wiring directly on the EJ22. Anyone know of any issues with that? Do both engines use the same sensors, etc. since they're both OBD-II?

 

As for using an older EJ22, I think I read somewhere that you can retrofit them with the necessary electronics from an OBD-II car, but it involves swapping cam and crank sensor wheels (pulleys?) among other things. I could easily be remembering this wrong though, so do more research if this option interests you.

[idosubaru]

are you sure you want an engine swap for mild piston slap? from what i've read piston slap isn't a big issue really. might want to read up on it some if you haven't as except for the noise it's not much of an issue from what i've read here on the boards. if you already know that...then pardon the rambling!