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Xuenan 02-08-2012 06:15 PM

2.5 intake manifold on a 2.2 engine
I dnt kno if this is a good idea or if it will even work but would there be any up sides to this idea or would it not work at all?

lulzcow 02-08-2012 07:35 PM

Downsides - 2.5 intake manifold is set up for the EGR system. You will have to seal that up to run on a 2.2 block. The previous owner of my 2.5 had done that, and after using it on his 2.2 for a while switched it back to the 2.5 I have. Which means I can't replace the EGR. I think they are ported about the same, so besides giving yourself some trouble I don't believe there would be any real difference.

johnegg 02-09-2012 05:20 AM

it wont fit on the 90 - 98 ej22s, it will on the phase 2 ej22. 99 - 01 the intakes are the same.

987687 02-10-2012 03:06 PM

Even if it did fit, there's no point, you wouldn't see any gain.
The only thing I can think that might be different are the injectors, swap them.

And for the note, 2.2 engines come with and without EGR. Depends if it's auto or manual.
Also, EGR has nothing to do with the block, the port is in the heads.

johnegg 02-10-2012 04:56 PM

in the 90s the ej22 and the ej25 are different. they may look the same, but they are a different size/shape/contour. this is a fact.

in the 00s the phase 2 ej25 and the phase 2 ej22 are the same size and will bolt on the other block. regardless of how different they may look the block dimension are the same and the mating surfaces are the same. this i have heard from reliable sources.

edit: im not familiar with the 00 ej22 but the 00 - 01 ej25 do not have EGR.

987687 02-10-2012 05:13 PM

The DOHC all have EGR. My family has a 99 outback 5mt that has EGR. The 2.2 only has EGR on the auto

987687 02-10-2012 05:18 PM

Phase 1 ej22 is SOHC and the spark plugs do not go through the valve covers. The valve covers are a funny shape.
Phase 1 ej25 are all DOHC.
The intakes do not swap.

Phase 2 ej25 and ej22 are both SOHC, both have flat valve covers with plugs that go through the valve covers. And the flange for the intake manifold is the same between the heads. The only really obvious way to tell the difference between the 2.2 and 2.5 is to look on the block where it'll say EJ22 or EJ25.

987687 02-10-2012 05:43 PM

Those pictures don't really show a lot of detail.
But I can see that the first picture doesn't have the torque box, and does have EGR. So it's probably a 96 or so with an automatic.
No later than 97, because I see it has a front canister. 98 did away with it.
And the second picture does have the torque box and doesn't have EGR, so it's probably a 98 or something with a manual. Doesn't have front canister. But someone has been messing with it, in that case. Because it doesn't have the cover thing over the crank gear for the timing belt. All manuals have that.

987687 02-10-2012 05:47 PM

They changed the shape of the intake manifolds slightly on the ones that have EGR. I don't know why, they just did.
Also, around 97 they must have run out of intake manifolds that didn't have the spot for EGR to bolt to. So on the manuals they just made a block off plate that bolts on there instead. That way they just had to make one style 2.2 intake mani, and bolt on the block off plate if it was for a manual.

987687 02-10-2012 05:55 PM

OK? I don't know what you're trying to get at with that.
What does it matter that it LOOKS LIKE an ej25 manifold? That doesn't mean it'll bolt to an ej25. Ej22s all have the same flange pattern. Regardless of what they look like.

phreich 03-01-2012 05:12 AM

I just replaced the short block on a blown 2000 SOHC2.5 (rod knock), with a mid-90's 2.2 block. I used the 2000's head and intake manifold, and used a head gasket kit for the 2000 2.5.

The only issue is the lack of a stud for the lower starter bolt. I plan on tapping the hole on the transmission bell housing for the lower bolt with an oversized tap (I think 12mm?) and then using an oversize bolt for the lower bolt hole on the starter.

Because I used the original heads and intake manifold, all the electronics carried over. I did move the crank timing belt sprocket from the 2.5 to the 2.2 because the car has a manual tranny and so the sprocket's tabs that are used to read rotation by the crank sensor are different. I also changed the timing belt tensioner bracket so I could use the improved tensioner from the later engine. Of course, I used the camshaft pulleys from the 2.5 that went with the 2.5 heads. I also used the 2.5 block's coolant "arch" that mounts on top of the block, because it uses a different temp sensor, and only has one instead of 2 temp sensors.

It all bolted up just fine and seems to be running fine.

The hybrid engine will have lower compression than the 2.5 did because of the shorter stroke and slightly smaller bore. However, the ECU from the 2000 should have no problem adjusting the fuel/air mixture to produce the proper richness for the engine.

I have read that one guy that did this has over 60K on his modified engine.

I hope this helps....

987687 03-01-2012 06:24 AM

Glad this worked for you!
I just want to clear one thing up.
You're correct that you had to change the crank gear, because the reluctor lobes are different.
This is not because it was an auto to manual swap, rather because in 99/00 with the new phase2 engine they changed it.

Not saying you did anything wrong, just clearing up WHY you had to the gear, so others don't get confused.

The coolant "arch" is better known as the coolant crossover pipe. Interesting you had to swap it, I hadn't heard that before. But I suppose it makes sense.

Lower compression = perfect candidate for a supercharger :D

phreich 03-02-2012 02:59 AM

Hi 987687,
A couple of questions about your comment about adding a supercharger....
1. I know that Subaru made turbo's for these engines. Any particular year(s) I should be looking for, and any issues surrounding adding one?
2. Any issues with the ECU and adding a turbocharger, or will the 2000 ECU "know" what to do with the increased airflow....
3. Any parts I will have to replace to do the conversion?
4. Any negative issues side-effects to expect?
5. Any suggested "howto" guides for doing this or suggested threads I should look at?
Thanks for the help!

987687 03-02-2012 05:34 AM

Adding a turbo, or for that matter, a supercharger isn't easy or straight forward.
It requires a lot of custom fabrication, then you have to find a way to tune the ECU. Use a fuel pressure unit (can't think of the right name at the moment), go aftermarket ECU, get a piggyback, etc.
You can't just slap forced induction on there.

I was partially kidding, but also partially serious because supercharger is something I've always wanted to do. It's a LOT of work though. But it's been done, and if you search around you'll find a bunch of information on it.
The general consensus is: It's cheaper to buy a car that already has a turbo on it, than to custom make a setup.
Which is both right and wrong. I have a friend who builds turbo subarus. He got a free obs (rusty as hell), and built a full turbo setup for it from spare parts in his garage. I think he has $150 into it.

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