So,
I have always been under the impression that the transition year for phase I to phase II on the Ej25 was '99. Last weekend I cracked open an Ej25 bottom end that turned that one upside down. The pistons were obviously phase I with the square cuts outs for the dish. But it has the bolt pattern for the 8 bolt mounting. It also has an end thrust crank bearing and bearing journals measure the right size for phase II. Ultimately is is a hybrid block. I personally didn't realize they went phase II so early. I know for sure this block came out of a '98 RS and it has never been apart before...

There was 2 phases of ej25 and two phases of dohc ej25. Some 99 legacies and foresters had interesting engine set ups in 99.

Russell,
I don't think you are getting it. I have never seen anything that suggested phase II bottom ends were used in '98. Everyone knows about the phase II's with DOHC's in '99.

Furthermore, the thing about the '99 with DOHC's is that they supposedly used the phase II pistons. It wasn't a hybrid block, to my understanding. It was only the DOHC used on the new bottom end. I could be mistaken on that, and that they were hybrid like this, but I have never heard of that...

good find matt! was this because of phasing out of things? why would they use such a mix? think theres something similar thru the 2.2 series?

98-99 was a meshing of technologies. The phase/year difference really isn't a solid line.

Assuming the block was a EJ25 --- 99's had square reliefs in the piston faces even on SOHC motors... they were just 1mm less deep than the 98's. The 98's and 99's were the same compression, 9.7:1, and the 00+'s were all 10:1.

I have NOT seen a phase 1 bottom end with 10:1 pistons, however. This is the only hybrid I haven't seen.

I have in my garage (read carefully) a phase 2 block that has had factory machining for phase 1 internals (bearings and all). It was probably the most screwed up thing I've ever seen.

Phase 1 Phase 2
-------------------Always------------------------
Crank Bearing Journal 48mm 52mm
Crank Thrust Bearing Center Rearmost
Ridges on WP Channel No Yes
--------------Most of the time-------------------
# of Trans Studs 1 2
Can't remember anything else...

Russell,
I don't think you are getting it. I have never seen anything that suggested phase II bottom ends were used in '98. Everyone knows about the phase II's with DOHC's in '99.

Furthermore, the thing about the '99 with DOHC's is that they supposedly used the phase II pistons. It wasn't a hybrid block, to my understanding. It was only the DOHC used on the new bottom end. I could be mistaken on that, and that they were hybrid like this, but I have never heard of that...
I understand what you are asking. I merely said exactly what I know about the topic. I have a legacy with phase 1 block and dohcs from 99. I know no more. I was just putting in what I knew. But interesting find on youyr part.

they just couldnt make it simple with the phases could they...............

Well, you have to understand manufacturing economics to understand why they mixed stuff up so much. If you have 100 phase 1 blocks laying around that just cost you $40,000, you don't just throw them out, you figure out how to use them.

Makes total sense to me. The people that I really think that this may benefit are the guys doing the Ej25/Ej22 hybrid franken-builds. If you can find one of the hybrid blocks with the phase II bearing placement, but still keep the slightly lower CR, it should put you right around 10.8:1 with the Ej22 heads. And ultimately, when you are shopping, it appears that what you may really need to be looking for is the bolt count on the case. It won't require going inside the block and measuring anything. You really could score if you shop smart, since phase I blocks tend to go for $75-125 while phase II are $200-400 each. If the seller doesn't know it is phase II, because of the year, you could really grab a good deal on a bottom end...

wow thats really interesting. What are the differences between phase I and phase II botom ends? is one crank balanced better than the other or is it built stronger/ better materials? Phase I and Phase II motors all together. What are the differences? Is one particularly better than the other?

And ultimately, when you are shopping, it appears that what you may really need to be looking for is the bolt count on the case. It won't require going inside the block and measuring anything.Not totally true, phase 1 blocks also have higher trans bolt counts in the later years, so that is rather unreliable. If you're referring to the trans stud counts, the same can be said there... you can remove/add trans studs at will. This is why I didn't include it my little grid above.

Matt,

1996 was the first year for the 2.5 in the US, it is a phase one all the way.

1997 through early 1999 were phase one motors with a different crank than the 1996 motor.

Early 1999 and up all use the phase two blocks weather it be a SOHC or a DOHC. The DOHC motors are "above" the deck with a square dish and the SOHC motors are "below" the deck with a round dish. I am talking 2.5L here :)

I have never seen a phase one block with the extra bolt holes for the tranny, but Subaru is full of supprises.

Another way to tell if the short block you are looking at is a phase two is by the rods. On the phase one, the rod cap has an even radius where the phase two rod cap has a large flat spot between the bolts. The counter weights on the two cranks are also shaped differently.

I started my Subaru engine building with these 2.5L n/a motors and have seen many different configurations, and I think that someone at Subaru gets a bonus for redesigning their aluminum bits that go on the 2.5L :)

Quirt Crawford

I have never seen a phase one block with the extra bolt holes for the tranny, but Subaru is full of supprises.
Strange. Just about every phase 1 EJ25 I have taken apart had all six bolt holes for the trans, plus an extra where a stud would be on the bottom, and only one stud on the bottom other side.

You are defining the phase change by the crank journal size & thrust bearing placement changes, right?

Strange. Just about every phase 1 EJ25 I have taken apart had all six bolt holes for the trans, plus an extra where a stud would be on the bottom, and only one stud on the bottom other side.

You are defining the phase change by the crank journal size & thrust bearing placement changes, right?


Yes, The rear thrust block is the one we refer to as a phase two.

As for the bolt holes in the block for the tranny, it's a Subaru, all bets are off :)

Quirt Crawford

Quirt,
Based on your information, that really does make this one an outlier. This block is definitely a '98. It was the factory block originally delivered in Mark Rameriz's RS. I am guessing that makes his car a late production '98 that just slipped through with the newer bottom end. It's so hard to tell what they were doing, with the RS being a new model for '98 and only a couple of hundred units produced that first year.

I have heard some weird tales over the years of mixed up cars. I have seen guys get JDM engines with STi heads, and even STI engines with two different spec heads on each side. It seems that Subaru just uses what they've got on hand as they wind down or ramp up a model year...

Quirt,
Based on your information, that really does make this one an outlier. This block is definitely a '98. It was the factory block originally delivered in Mark Rameriz's RS. I am guessing that makes his car a late production '98 that just slipped through with the newer bottom end. It's so hard to tell what they were doing, with the RS being a new model for '98 and only a couple of hundred units produced that first year.

I have heard some weird tales over the years of mixed up cars. I have seen guys get JDM engines with STi heads, and even STI engines with two different spec heads on each side. It seems that Subaru just uses what they've got on hand as they wind down or ramp up a model year...

Matt,

The tenth digit of vin number that lives on the drivers "side" of the block denotes the year the block was produced. On the 1999 rear thrust blocks the didgit will be an X, 1998 will be a W and the 1997 will be a V.

If you need some of these blocks, give us a call. Most of the time we sell them for scrap.

Quirt Crawford
www.crawfordperformance.com

As for the bolt holes in the block for the tranny, it's a Subaru, all bets are off :) You know, now that I think about it, I've never seen a block with phase 1 heads and the greater number of trans bolt holes, and vice-versa. I bet that is what really denotes the trans bolt hole changes.

You know, now that I think about it, I've never seen a block with phase 1 heads and the greater number of trans bolt holes, and vice-versa. I bet that is what really denotes the trans bolt hole changes.


Do yourself a favor and don't loose any sleep over it :) and keep us posted with any new info.

Quirt

Do yourself a favor and don't loose any sleep over it :) and keep us posted with any new info.

QuirtWell, I am a little disturbed, honestly. I've had fairly different encounters than you have, and I know what I was seeing was true. I am pretty sure I haven't had as many EJ251's open as you, too... I'm only up around the 15-20 level. *shrug*

Hmmmm....interesting thread. Now I know why Matt M. asked me a question on another forum.

Matt, I will know for sure next weekend, it's time for HG's and a clutch in mine.

Quirt is the man!

Well, I am a little disturbed, honestly. I've had fairly different encounters than you have, and I know what I was seeing was true. I am pretty sure I haven't had as many EJ251's open as you, too... I'm only up around the 15-20 level. *shrug*

Your encounters are probably closer to mine now that I have edited my above posts :o

Please don't be disturbed by my statments. :) Like you, I am just relaying what I have seen. And when it comes to Subaru, it's not the gospel, it's just a case of the particular parts they happened to assemble that day.

Quirt Crawford
www.crawfordperformance.com

P.S. JonofScio, Thanks for the kind words :)

Quirt,
Thanks for the offer on the blocks. I have more blocks sitting around than I need these days. We were actually just tearing this one down to find out the point of failure. We wanted to be sure that our high compression franken motor hadn't failed from the choice of the build. And we were prooven correct. The block failed because it had been terribly abused, not because the build was a bad combination of parts...

"Early 1999 and up all use the phase two blocks weather it be a SOHC or a DOHC. The DOHC motors are below the deck with a square dish and the SOHC motors are above the deck with a round dish. I am talking 2.5L here " Quote from Quirt.


i got my EJ25 shortblock form a 98' outback, the piston dishes are square. does this mean that my block's pistons dont extend beyond the deck surface? from what Quirt says it sounds like it. is there anyway i can definetely tell which phase block i have? im guessing form the center thrust bearing right? please tell me i dont have to cranck the block to tell. i dont want to make my frankenstein thinking ive got 10.8:1 Cr, and finding out ive got less than stock.


~Josh~

hey, I was only stating an obvious fact. anybody who has a business like CP, has to be good at something for a reason.

"Early 1999 and up all use the phase two blocks weather it be a SOHC or a DOHC. The DOHC motors are below the deck with a square dish and the SOHC motors are above the deck with a round dish. I am talking 2.5L here " Quote from Quirt.


i got my EJ25 shortblock form a 98' outback, the piston dishes are square. does this mean that my block's pistons dont extend beyond the deck surface? from what Quirt says it sounds like it. is there anyway i can definetely tell which phase block i have? im guessing form the center thrust bearing right? please tell me i dont have to cranck the block to tell. i dont want to make my frankenstein thinking ive got 10.8:1 Cr, and finding out ive got less than stock.


~Josh~

Sorry, I had a brain fart :) Your pistons will be above the deck, and your block will have four mounting points to the tranny on a phase one block.


Quirt Crawford
www.crawfordperformance.com

Quirt,
So does that mean that one could use the newer 4-layer thin head gasket on a phase I for a marginal bump in compression? I know how you feel about the timing issues, but beyond that...

Quirt,
So does that mean that one could use the newer 4-layer thin head gasket on a phase I for a marginal bump in compression? I know how you feel about the timing issues, but beyond that...

Matt,

Please re-read my prior posts as I have done a good job of misleading you :o

Quirt Crawford
www.crawfordperformance.com

OK,
That's what I was thinking. I see your edit...

OK,
That's what I was thinking. I see your edit...

Sorry for the wild goose chase :)

Quirt,
Since I have your attention; what pistons do you offer for the NA Ej25's? What sort of different compression ratios do you sell?

Quirt,
Since I have your attention; what pistons do you offer for the NA Ej25's? What sort of different compression ratios do you sell?

Matt,

We do not stock any "off the shelf" pistons from CP, they are all custom made to the application. That being said, we will make you pistons with the compression ratio to suit "your" needs.

Thanks,

Quirt Crawford
www.crawfordperformance.com

Matt,

We do not stock any "off the shelf" pistons from CP, they are all custom made to the application. That being said, we will make you pistons with the compression ratio to suit "your" needs.

Thanks,

Quirt Crawford
www.crawfordperformance.com

That is quite cool. I imagine the prices are as well...

All right,
Let me re-phrase the question. What compression ratio would you suggest for a car that will be running 91 octane pump gas, ported heads, and a reflash from Bill at I-speed? I was thinking around 11.5:1. Since I live at 5000ft and rarely if ever take it below 3500ft, I can get away with a bit more than flatlanders.

All.....I just removed the heads from my car.

History....."Overnight rebuild wonder" in the late spring of 2004. Put 5252 miles on it over the next week or so (Matt M was there for a lot of those miles).

HG's went again (sigh).

Soooo......engine out and working on it.

Engine was from a 99 Forester, 2.5L NA.

Verified the rear thrust bearing (indicating phase-II).

Pistons have the square dish relief and they protrude a bit beyond the block deck.

Heads are DOHC.

so yur HG's didnt even last you a year? damn. how did you manage that?

so yur HG's didnt even last you a year? damn. how did you manage that?
Ummm....1.5 years and ~52K miles.

Other than that, I don't know for sure although it is a 3 layer HG, not a newer 4 layer.
A new set of 4 layer going in.

And Charlie drives that car like he stole it...

And Charlie drives that car like he stole it...
and.....ummmmm....how would you know that since I live in NJ and you are in CO????? :banana: :lol: :devil: :D

OK, I will ask this here.....

I am about ready to reassemble my hybrid/mid year phase-II/I engine.

It is DOHC (phase-I) with a phase-II block.

I am using the newer 4 layer head gaskets.

Should I use the "standard" torque method, or has SOA come up with something different?

:confused: :cool:

bump for head torque comments for the newer HG's on a DOHC and phase-II block.

and.....ummmmm....how would you know that since I live in NJ and you are in CO????? :banana: :lol: :devil: :D

Maybe because I have travelled with you, and was in the car when you ran out of gas like a hood rat in a jacked car... :confused:

you have a new mail about head torque...

Maybe because I have travelled with you, and was in the car when you ran out of gas like a hood rat in a jacked car... :confused:

you have a new mail about head torque...
(shhhhhhh.......nobody else knew that.) ;)

As to the mail, thanks, I have read it (although I still can't see that other place when I am at work :mad: )

All right,
Let me re-phrase the question. What compression ratio would you suggest for a car that will be running 91 octane pump gas, ported heads, and a reflash from Bill at I-speed? I was thinking around 11.5:1. Since I live at 5000ft and rarely if ever take it below 3500ft, I can get away with a bit more than flatlanders.

Sorry Matt, I have been out of town :)

I have not been involved in a motor project like the one you are speaking of. That being said, your altitude will most likley let you run the 11.5 to 1 compression ratio.

That's the best I can do for a suggestion on your compression ratio ;)

Quirt Crawford
www.crawfordperformance.com

okay, heres another hybrid question. is it possible to run 89 octane gas with 10.8:1 CR? im at about 500 feet above sea level. going to use phase II EJ22 heads and phase I EJ25 bottom end.



~Josh~

okay, heres another hybrid question. is it possible to run 89 octane gas with 10.8:1 CR? im at about 500 feet above sea level. going to use phase II EJ22 heads and phase I EJ25 bottom end.



~Josh~

This is a question that is better suited for an existing hybrid owner :)

Quirt