Hybrid build question.

[98legacygt22]

So I know the combination I am thinking of will work but I just wanted to know if I would need a thicker head gasket or anything like that. The compression will lower but it shouldn't lower as much as if I used a phase 1 EJ22 short block. The phase 2 ej22 is 10:1 from the factory vs 9.5:1 like the phase 1 EJ22E and it would still leave room for boost some day down the road and I should still have ok off boost power.


1998 EJ25D heads
1999 EJ222 phase 2 short block

Also, where should I buy new piston rings from? I suppose go straight to the dealership.

[86bratman]

You're going to have a high compression engine, something in the neighborhood of 10.3-10.4:1. The reason for this is that not only are the pistons different in the ej222, the heads also have a larger combustion chamber than phase 1. The phase2 ej22 and ej25 heads have the same combustion chamber size at 50cc. The 97-99 ej25d heads are 47cc.

[1996Battlewagon]

EJ22D has done this. I believe more than once.

viewtopic.php?f=31&t=26171 (https://sl-i.net/FORUM/viewtopic.php?f=31&t=26171)

[86bratman]

I haven't done the ej222 short block, but I've built two from ej22e's one low comp for a turbo in a buddy's car, one with eg33 pistons for high compression for my car. I did all the figures to check out all the options when I decided to do the high comp one. I decided to go the route I did for ease of parts, ej222's are impossible to find out here.

[98legacygt22]

You're going to have a high compression engine, something in the neighborhood of 10.3-10.4:1. The reason for this is that not only are the pistons different in the ej222, the heads also have a larger combustion chamber than phase 1. The phase2 ej22 and ej25 heads have the same combustion chamber size at 50cc. The 97-99 ej25d heads are 47cc.

Ah well thats better news. No need to bother with going turbo then. I'll just put in new piston rings and main/rod bearings and run it. Maybe some delta grind cams and a tuner. Just bought a Snap On digital torque wrench so I can finally do internal engine work correctly.

But do you think I should use a thicker head gasket so there is no interference? I don't think I will need to but I'm not 100% positive

[86bratman]

Running the ej25d heads you're going to have an interference engine no matter what you do. They are not only piston to valve but valve to valve do to the valve angle. Only a problem if you have a skipped timing belt or something like that. I wouldn't worry about a thicker gasket, I've got a stock thickness head gasket with my eg33 pistons, which have a slightly taller dome than ej222, and have no issues.

[98legacygt22]

Running the ej25d heads you're going to have an interference engine no matter what you do. They are not only piston to valve but valve to valve do to the valve angle. Only a problem if you have a skipped timing belt or something like that. I wouldn't worry about a thicker gasket, I've got a stock thickness head gasket with my eg33 pistons, which have a slightly taller dome than ej222, and have no issues.

Ok cool. I've timed tons of EJ25's so I know I'm all set. I wonder which head gasket I should order. I may have to contact Cometic and have them make custom ones for me.

[86bratman]

The victor reinz ej222 head gaskets are what I'd recommend, they're an mls gasket and have the right coolant passages.

[98legacygt22]

The victor reinz ej222 head gaskets are what I'd recommend, they're an mls gasket and have the right coolant passages.

Yeah and they make good stuff, I've used their gaskets before. I'm contemplating on also rebuilding the 2.2's bottom end. It has some miles on it, I was thinking new rings and new lower end bearings.

[86bratman]

Be careful buying rings if you go ej222, theyre different that ej22e and a lot of places don't make the distinction.

1999 Subaru Impreza 2.2:

Uses different piston rings than previous EJ22s. 1.2/1.2/2.5 as opposed to the standard of 1.2/1.5/3.0 for the ring width. See; Hastings 2C5167. I got mine from RetroRoo (ShawnW)

Taken from this thread http://www.ultimatesubaru.org/forum/top ... 2+%2Brings (http://www.ultimatesubaru.org/forum/topic/134782-beginning-of-comprehensive-guide-to-ej22-differences-among-model-years/?hl=%2Bej22+%2Brings)

The RetroRoo shop he speaks of has a website http://retroroo.com/ owner is a super nice guy, and also owns the ultimate subaru message board that thread was from.

[98legacygt22]

Be careful buying rings if you go ej222, theyre different that ej22e and a lot of places don't make the distinction.

1999 Subaru Impreza 2.2:

Uses different piston rings than previous EJ22s. 1.2/1.2/2.5 as opposed to the standard of 1.2/1.5/3.0 for the ring width. See; Hastings 2C5167. I got mine from RetroRoo (ShawnW)

Taken from this thread http://www.ultimatesubaru.org/forum/top ... 2+%2Brings (http://www.ultimatesubaru.org/forum/topic/134782-beginning-of-comprehensive-guide-to-ej22-differences-among-model-years/?hl=%2Bej22+%2Brings)

The RetroRoo shop he speaks of has a website http://retroroo.com/ owner is a super nice guy, and also owns the ultimate subaru message board that thread was from.

Ok cool. I was planning on going straight to the Subaru dealership but I will keep that in mind. It has good compression but also has pretty high miles (or so I think, the PO took good care of it and it ran great but was just slow as a turd). You think an 06 STI oil pan and pickup would be a good idea? I'm thinking that route because it has more baffles in it so I'd be less likely to starve the engine of oil while cornering hard.

[EJ22D]

My very first hybrid build was a 25D head/222 block hybrid & when you are all set & done, that engine should have anywhere from 10:1 to 10.5:1 depending on gasket thickness alone. The heads that have to be used MUST be the 97-99 25D heads as they, combined with the completely flat topped pistons, will create a high compression engine. I estimate my current 25D/22E hybrid to produce about 150bhp so the 25D/222 hybrid should produce about 165/170bhp (yes, there is THAT much of a power boost from the regular 22E or 222.)

That engine will run as smooth as molasses & it will LOVE to be revved. Depending on mods, that engine will also rev fairly quickly, as it has a shorter stroke than the EJ25. You won't miss the 25D at all. This engine is VERY Honda-like but at the same time, retaining enough of it's low-end that it will tolerable when you are in the city streets keeping up with traffic. I loved my 222 hybrid & the 5 speed just adds to the fun factor but if you have an auto with the power mode mod, it will be just as fun to rev up. You will need to use the 222 Victor Reinz or Cometic hybrid gasket for this build.

[98legacygt22]

My very first hybrid build was a 25D head/222 block hybrid & when you are all set & done, that engine should have anywhere from 10:1 to 10.5:1 depending on gasket thickness alone. The heads that have to be used MUST be the 97-99 25D heads as they, combined with the completely flat topped pistons, will create a high compression engine. I estimate my current 25D/22E hybrid to produce about 150bhp so the 25D/222 hybrid should produce about 165/170bhp (yes, there is THAT much of a power boost from the regular 22E or 222.)

That engine will run as smooth as molasses & it will LOVE to be revved. Depending on mods, that engine will also rev fairly quickly, as it has a shorter stroke than the EJ25. You won't miss the 25D at all. This engine is VERY Honda-like but at the same time, retaining enough of it's low-end that it will tolerable when you are in the city streets keeping up with traffic. I loved my 222 hybrid & the 5 speed just adds to the fun factor but if you have an auto with the power mode mod, it will be just as fun to rev up. You will need to use the 222 Victor Reinz or Cometic hybrid gasket for this build.

What's up Ken? lol and yeah I was also contemplating on tossing in new rings but the 2.2 has so much compression that I cant turn it by hand so that's a good sign. I'm going to swap to an sti oil pick up and oil pan for hard cornering purposes. I was thinking of possibly getting the cams ground by delta and (depending on cost) having the heads port and polished. It should be quicker than the stock EJ25D I imagine.

[86bratman]

What year sti pickup are you thinking about running? Some years(and I can't remember which exactly, like 06+) have a problem of cracking and losing oil pressure, not a good thing many spun rods. If you're going to do an upgraded pickup you should probably pop for one of the killer b pieces.

[EJ22D]

What's up Ken? lol and yeah I was also contemplating on tossing in new rings but the 2.2 has so much compression that I cant turn it by hand so that's a good sign. I'm going to swap to an sti oil pick up and oil pan for hard cornering purposes. I was thinking of possibly getting the cams ground by delta and (depending on cost) having the heads port and polished. It should be quicker than the stock EJ25D I imagine.

I'm good. Participating in a study that will yield some change for me to revive my LGT with a manual transmission swap that will in turn, yield some boosted or H6 goodness, depending on what I am in the mood for when the time comes. If I stay with the H4, I will definitely maintain my grip on the EJ22 out of being an EJ22 enthusiast.

STi oil pan w/Killer Bee pickup sounds like a pretty nice combo, if you ask me. Have you continued
on the quest to DOHC the EJ22 or are you going to boost it in stock form? If you do that, it WILL be faster than a 25D for sure but the 25D heads bring out more potential.

[98legacygt22]

What's up Ken? lol and yeah I was also contemplating on tossing in new rings but the 2.2 has so much compression that I cant turn it by hand so that's a good sign. I'm going to swap to an sti oil pick up and oil pan for hard cornering purposes. I was thinking of possibly getting the cams ground by delta and (depending on cost) having the heads port and polished. It should be quicker than the stock EJ25D I imagine.

I'm good. Participating in a study that will yield some change for me to revive my LGT with a manual transmission swap that will in turn, yield some boosted or H6 goodness, depending on what I am in the mood for when the time comes. If I stay with the H4, I will definitely maintain my grip on the EJ22 out of being an EJ22 enthusiast.

STi oil pan w/Killer Bee pickup sounds like a pretty nice combo, if you ask me. Have you continued
on the quest to DOHC the EJ22 or are you going to boost it in stock form? If you do that, it WILL be faster than a 25D for sure but the 25D heads bring out more potential.

Probably no boost due to how high the compression ratio will be, if it's near 10.5:1 I could only run like 5 psi

[EJ22D]

What's up Ken? lol and yeah I was also contemplating on tossing in new rings but the 2.2 has so much compression that I cant turn it by hand so that's a good sign. I'm going to swap to an sti oil pick up and oil pan for hard cornering purposes. I was thinking of possibly getting the cams ground by delta and (depending on cost) having the heads port and polished. It should be quicker than the stock EJ25D I imagine.

I'm good. Participating in a study that will yield some change for me to revive my LGT with a manual transmission swap that will in turn, yield some boosted or H6 goodness, depending on what I am in the mood for when the time comes. If I stay with the H4, I will definitely maintain my grip on the EJ22 out of being an EJ22 enthusiast.

STi oil pan w/Killer Bee pickup sounds like a pretty nice combo, if you ask me. Have you continued
on the quest to DOHC the EJ22 or are you going to boost it in stock form? If you do that, it WILL be faster than a 25D for sure but the 25D heads bring out more potential.

Probably no boost due to how high the compression ratio will be, if it's near 10.5:1 I could only run like 5 psi

If it's that high, I wouldn't even bother boosting it. Just set your brakes & suspension around that engine's output. A wise man once said that it is more fun to drive a slow car fast than it is to drive a fast car slow & trust me, that hybrid will have more pickup than you think when you make it sing.

[98legacygt22]

What's up Ken? lol and yeah I was also contemplating on tossing in new rings but the 2.2 has so much compression that I cant turn it by hand so that's a good sign. I'm going to swap to an sti oil pick up and oil pan for hard cornering purposes. I was thinking of possibly getting the cams ground by delta and (depending on cost) having the heads port and polished. It should be quicker than the stock EJ25D I imagine.

I'm good. Participating in a study that will yield some change for me to revive my LGT with a manual transmission swap that will in turn, yield some boosted or H6 goodness, depending on what I am in the mood for when the time comes. If I stay with the H4, I will definitely maintain my grip on the EJ22 out of being an EJ22 enthusiast.

STi oil pan w/Killer Bee pickup sounds like a pretty nice combo, if you ask me. Have you continued
on the quest to DOHC the EJ22 or are you going to boost it in stock form? If you do that, it WILL be faster than a 25D for sure but the 25D heads bring out more potential.

Probably no boost due to how high the compression ratio will be, if it's near 10.5:1 I could only run like 5 psi

If it's that high, I wouldn't even bother boosting it. Just set your brakes & suspension around that engine's output. A wise man once said that it is more fun to drive a slow car fast than it is to drive a fast car slow & trust me, that hybrid will have more pickup than you think when you make it sing.

Well... 5 psi never hurt anyone lol. I can lower the compression slightly with EJ25D head gaskets and that would be enough for 5 psi or so safely.