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OBW EJ22 SOHC to EJ25 DOHC swap question.


darkducati
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New to the forums here and have a question. Yes, I have searched the net throroughly and found different answers so I would like to get a second opinion. From what I have read I can swap an EJ25 DOHC into my OBW using the EJ22 harness, ECM, throttle body, and IAC valve while keeping the 25 complete with sensors, injectors, and exhaust/cats. Can anyone confirm this? Is there anything else thats needed?

 

To go ahead and answer the next question a freind had the car with the EJ25 and it was hit in the rear. The engine had head gaskets replaced and was serviced about 10k miles ago and was basically free. The EJ22 in the car has a head gasket that is leaking into the cooling sysem and over 300k miles so that is the reason for the swap.

 

Thanks for any help anyone can provide!

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impossible to answer without knowing what vehicle/year.

 

this is not a direct swap for 1990-1994 or 1999+ EJ22. that's probably why you're confused because the answer to your question (if it's a 1995-1998 EJ22) is "yes" it's a plug and play swap.

 

since you have the entire car you can swap the exhaust manifold with it if you have too. 95 EJ22 won't need it swapped - anything else will - but it's really easy since you have to unbolt the manifold from the engine anyway to pull the motor. after that it's like 3 or 4 more bolts to get the entire manifold off and put the EJ25 onto the EJ22 vehicle. bolts right up.

 

engine drops in and plugs in, nothing to it, just an engine swap.

 

if both EJ22 and EJ25 have EGR (the EJ25 will have it, EJ22's can vary) - then it's the same. if the EJ22 doesn't have it then everything still works fine but you'll need to work around that (easy).

 

use your EJ22 flexplate on the EJ25 engine if it's an auto.

 

powersteering lines just kind of hang there because the mounting points are different - but no big deal.

 

if it's a 1998 or 1999 DOHC then the bellhousing bolt pattern is different than earlier EJ22's but still bolts up and works just fine.

 

telling us what year you're talking about will help distinguish these details.

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You would be swapping in a VERY problematic engine in place of your super reliable 2.2. The EJ25D is very troublesome. You absolutely should NOT do this. It's a bad idea and will ruin the value of the 96 OWB 5 speed. That's a rare single-year model and highly desireable. If you want the problem engine then sell it and buy a 97 to 99.

 

HUGE fail to get 30 HP.

 

GD

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You would be swapping in a VERY problematic engine in place of your super reliable 2.2. The EJ25D is very troublesome. You absolutely should NOT do this. It's a bad idea and will ruin the value of the 96 OWB 5 speed. That's a rare single-year model and highly desireable. If you want the problem engine then sell it and buy a 97 to 99.

 

HUGE fail to get 30 HP.

 

GD

Did you read my post? I'm not doing this for 30HP.

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The 98 EJ25 will have EGR so if your 96 does have EGR it's simple.

Still works, swaps, runs just fine if it doesn't have EGR you just might need to plug up the EGR ports/solenoid or leave them for decoration?! lol

 

No need to swap computers - EJ22 ECU will run it just fine. I've swapped ECU's on EJ swapped vehicles and noticed zero difference at all, I wouldn't bother.

 

98 has a different bolt pattern but don't let it fool you - still bolts right up, no big deal.

 

You'll need to swap the exhaust manifold from the 98 onto the 96.

 

For auto's you need to retain the EJ22 flexplate, the flywheel is currently eluding me.....

 

 

I'd prefer the EJ22 as well without a thought. You could sell or trade the EJ25, they are easily sold due to multiple failures creating a steady demand for them.

 

If you were interested read about EJ25 head gaskets, bottom end bearing failures, and DOHC valve adjustments/burnt valves. The 96 will have about a $100 cheaper timing belt kit too.

 

All EJ25's are interference, and while most 96 EJ22's are supposed to be non-interference I've heard reports that some are not - like a recently bent valve EJ22 on another forum.

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Okay cool. Thanks for the help. Since the headgaskets and timing belt were done 10k miles ago I think I'll try and run it. I will likely take a look at the EJ22 and if it doesn't have a cracked head I may rebuild it. With 330k+ miles I'm sure it needs it and it leaks from everywhere there is a seal. It uses about 1/2 gallon in just 15 miles and runs on 3 cylinders so its pretty bad. If the short block is unhurt I my rebuild and use it for a frankenstein engine if there is head damage. Thanks again for the help!

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So I'm in the middle of this swap and things kind of off. The throttle body and IAC seem to be identical to the 2.2 down to the part numbers and connectors. The coil and knoxk sensor however are different. The knock sensor connector isn't the same but I can swap over the original 2.2 unit. No biggie. The coil however is completely different. The connector is different, the outputs are female on the 2.2 vs male on the 2.5 and its a different size so it won't bolt on to the 2.5 intake. Are the pinouts the same so I can just swap the connector? Any ideas on why they're different?

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I've had that happen with the coils.

 

Luckily I have enough parts around. If you swap coil and wires you're golden from another 2.5. From a 2.2 I'm not so sure.

 

WHen I've done this the coil connector to the ignitor was the same, but the sex of the plug wires was different.

 

You get in a jamb let me know. I'm putting stuff on Ebay and believe I have a box dug out with coil and pretty new factory wires - don't remember the sex of the coil but doesn't matter if you've got the matching wires.

 

And I should have many sets of coil and plug wires that are the normal ones.

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Also the coil off the old engine should work (generally 2.2 and 2.5's seem to be the same) and just get different sexed plug wires. Unfortunately the OEM plug wires are highly recommended on a 2.5 and somewhat pricey.

 

If the 2.2 plug wires will reach no harm in trying unless someone else pipes in with a no.

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  • 3 years later...
  • 4 months later...

Doing Exact swap, 1996 Manual Legacy L with a Ej22 178k little to no compression in cylinders 3 and 4, bought an Automatic 1998 Forester w. EJ25 and 90k rotted undercarriage. Pulled both motors, doing timing. head gaskets. new clutch n flywheel before I drop the Ej25 in to bolt up to my manual transmission. I want to make sure to do this 100% full Ej25D swap without having to take the 93 octane Ej22 heads on ej25 block route. Are the Wiring Harnesses completely the same? And will my Ej22 have the opposite sex coils or same as the Ej25

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Will this pass smog in CA? 2.5 DOHC with the 2.2 heads ? I have a 98 subaru legacy outback. 2.5 and a bad value. Have 2.2 heads.

 

looks like this was never answered but i don't know - the only way it'll fail is if they visually know how to inspect the mechanical components.  it'll pass all electrical and emissions test if done properly.

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 I want to make sure to do this 100% full Ej25D swap

 

Install EJ25 with EJ25 flexplate (if auto) and EJ25 exhaust manifold.

Block off EJ25 EGR tube if the 97 doesn't have EGR - which manuals often do not (complete EGR info in link below).

DONE - your questions aren't needed.

 

Coil pack doesn't matter - EJ25 plug wires and EJ25 wiring harness that plugs into the EJ25 coil pack.  Whether the EJ22 is the same is immaterial.

 

Everything you need to know is right here:

http://www.ultimatesubaru.org/forum/topic/153118-ej22-or-ej18-swap-into-ej25d-dohc-vehicle/

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