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What EJ25 Block will sync up w/ EJ222 (Phase 2) Heads?


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So, with the '00 OBS I just bought I have 90% of the story now and I know which direction I need to go.  And FYI I paid $700 for it with "parking lot dings" on the body and a normal wear (no tears) interior.  The previous owner to the one I purchased it from took great care of it.  The previous owner, well he was a kid that knew nothing about cars (including routine maintenance).

 

Long story short I'm 99% sure it has lower end damage.  Since that's the case I'm not looking for an EJ22 Phase 2 Block, they are hard to find anyways.  I have a potential line on an EJ25x (not sure which model) short block that was not knocking when removed.

 

I'm wondering which short blocks will line up with the EJ222 Phase 2 Heads/intake for a swap like this.

 

Also, which gasket set is going to work?  I usually go with a cheap gasket set + good brand head gaskets but the cheap gasket set doesn't cover the EJ22 Phase 2..................

 

Thanks in advance. :)

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blocks are pretty simple.

it is the heads and intake that are year specific.

lots will bolt up.

but 00 - 03/4 are probably going to be your best bet,

most powerful.

 

but 90 - 96 ej22s would be non-interference.

they only have 4 trans bolt holes but they will work.

as will the 96 - 98 ej25d, also only 4 bolt holes, and are interference

and the 97 - 98 ej22, also only 4 bolt holes, and are interference.

 

 

but 00 - 03/4 all have the 8 bolt holes and will bolt up.

 

not sure about the head gaskets,

and 90 - 98 blocks may require a specific gasket to avoid interference.

i do not know.

 

btw, the 99 outback ej25d uses a phase 2 ej25 block (00 - 03/4),

with a phase 1 DOHC heads (96 - 98).

this was standard from the factory.

Edited by johnceggleston
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Well I'm going to look at what should be an EJ251 block this afternoon. It's already disassembled and needs the crank turned with new bearings. It's from an 04 outback. From what he said the pistons, rings, and cylinders are all in great shape.

 

So, if that's as he said all I need is to figure out what gaskets to buy.

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Ok, so after a ton of research it seems that when your pairing a Phase 2 EJ22 Head with a EJ251 or newer block they use the stock  head gasket.  

 

So what is the best head gasket for this?  OEM or Aftermarket recommendations anyone?  Over at NASIOC they are commenting on the 05/06 STI head gaskets 11044AA642.

 

Any other recommendations and please include a reason behind the recommendation. :)

 

Thanks

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general consensus on here is to use turbo model head gaskets for them.

 

And I always thought interference followed the heads and not the block.

 

Technically any 1990-04 EJ block will work. I would be looking for 2000+ to keep it simple. I believe the head gaskets are the same for both phase 2 Ej22 and EJ25

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general consensus on here is to use turbo model head gaskets for them.

 

And I always thought interference followed the heads and not the block.

 

Technically any 1990-04 EJ block will work. I would be looking for 2000+ to keep it simple. I believe the head gaskets are the same for both phase 2 Ej22 and EJ25

 

I'm fairly certain it will be an interference motor no matter what block I use.  With an older block that doesn't have domed pistons I'm looking at more clearance between the valves and the pistons which means less damage and potentially easier to save, but would still probably cause damage.  But that's not something I'm concerned with considering the work I will be doing and I expect it to remain interference anyways. :)

 

So, an STI is turboed which means those gaskets should be fine. :)

 

The difference between using a Phase 1 Head and 2.5 Block or a Phase 2 Head and an older Phase 1 block is the coolant holes don't all line up between an EJ22 and EJ25 meaning you have to modify a stock head gasket or buy a hybrid gasket.

 

Using the Phase 2 EJ22 heads I already have on a EJ251 Block means I can go with a stock head gasket no problem.  

 

Basically I'm not exactly building a frankenmotor.  It will have a little more compression than a stock 2.5, but it will essentially be a 2.5 in place of a 2.2. :)  

 

Either way it's still an upgrade! :D

 

So far I've found that every gasket, except the exhaust gasket, lines up between an '04 Outback and the '00 Outback Sport.  This includes intake gaskets, valve cover gaskets, spark plug grommets, etc...  And I know the camshaft seals are the same.

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Little more info (and I'll add more as I get it for others).  I will be going from around 142hp to probably close to 170hp (stock is 165hp for an '04 outback).  And it will be going from around 149ft/lbs torque to 166 ft/lbs torque.

 

I've also read (but won't know until I drive it) that it should have a better power curve as well.

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