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Are all 8 bolt EJ25 blocks Phase 2?

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i just realized my EJ25 block for my frank build has the 8 mounting holes. The vin on the block is:4S3BG6856W7655075 - the VIN indicates it is a 1998 block, but doesn't the 8 bolt holes indicate this is one of the factory hybrids with the phase 2 block (larger rod bearings and thrust bearing moved to #3) with ph1 square dished pistons and ph1 dohc heads?

I guess it's possible that late model year 98s have a phase2 block. Do you know the manufacture date of the car the 2.5 came out of?

  • Author
Maybe. Phase-II is larger rods and #5 thrust. Pull the pan and look.

 

GD

 

Pan is off, engine is on my bench, what exactly am I looking for?

Hmmmm. Interesting. So I was just out in the garage. The original 2.5 from my 98 legacy is an 8 bolt bellhousing. Unfortunately I don't know the manufacture date of that car since I've sold it, but iirc it was early 98. I know for sure it had a 4 bolt bell housing, though. I can't figure out how to see where the thrust bearing is... All I can see from the bottom are crank and rods.

  • Author
Maybe. Phase-II is larger rods and #5 thrust. Pull the pan and look.

 

GD

 

Pan is off, engine is on my bench, what exactly am I looking for?

No reason for alarm, you have exactly what you thought you had - a 1998 Phase I EJ25.

 

doesn't the 8 bolt holes indicate this is one of the factory hybrids with the phase 2 block
No.

 

Re: Are all 8 bolt EJ25 blocks Phase 2?
No.

 

Either way it doesn't matter and will work...but I guess you want performance and want to know what kind of compression/power you're making and want it to be more of those.

  • Author
No reason for alarm, you have exactly what you thought you had - a 1998 Phase I EJ25.

 

No.

 

No.

 

Either way it doesn't matter and will work...but I guess you want performance and want to know what kind of compression/power you're making and want it to be more of those.

 

I just found this on the Forester forum posted by Ferret:

 

"The phase has to do with the crankshaft thrust bearing placement ( moved from center to rear ), changes to the internal oil passages, coolant passage shapes changed and 8 bolts between the transmission and the engine.

 

It has been loosely thrown around that phase II was SOHC only. Not true. I have a Subaru Tech Reference manual that describes this in detail."

 

As you state, it doesn't really matter to me, except for my own knowledge and the fact of it being a Ph1 or Ph2 block. I like the idea of the stronger internals too!

  • Author

FYI - I also found this out: Phase 1 ej25 blocks had two ridges next to the "japan" by the #1 Cylinder, Phase 2 blocks have a single ridge at that location.

 

Phase 2 - Single Ridge:

phase2blockid.jpg

 

Phase 1 - Double Ridge:

phase1block.jpg

 

These two blocks both are stamped W in the Vin on the side of the block.

 

Good information for anyone else trying to ID whether they have an early Phase 2 or Phase 1 block.

 

I assume since these were both out of 1998 Legacy outback wagons - the Phase 1 block has the early crank and the Phase 2 uses the updated crank. But they both have the the phase 1 pistons and heads.

 

Paul

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