2.2 vs. 2.5 SOHC

[thelynns]

Still trying to make an educated purchase of a newer Subaru. Seeing a lot of Foresters that are 2.5 and SOHC. Are these just as good as a 2.2 SOHC?

 

Thanks again, this site has been extremely helpful.

 

The Lynns

[edrach]

The EJ22 has been considerably more reliable than the EJ25 version (talking about SOHC only). However, the EJ25 can be a decent engine from a reliability viewpoint.

 

I only have anectdotal support for that. I bought our '99 Forester from an independent shop in Portland (www.fixmysuby.com) with the head gaskets already done along with timing belt service at 105K. Three years later, and with 155K the car is still running fine and without any engine related issues. (by the way, Superior Import Repair is owned by a USMB member).

 

I have a close friend who runs rallycross events with his '99 Legacy GT. I know he has an EJ25 engine (not sure if it's SOHC or not) and he's the original owner and his car went 158K before he had head gasket issues. He had the head gaskets done last year and hasn't had any issues since then.

 

Over the years, Subaru has addressed the head gasket issues and come up with gaskets and repair requirements that seem to have made the head gasket issue go away.

 

As to the comparison with the EJ22, understand that the EJ22 was a non-interference engine prior to 1997; after that SOA went to an interference version on the EJ22. All the EJ25 engines are interference types. This will only make a difference if you are unfortunate enough to have a timing belt failure.

Edited June 10, 2011 by edrach

[Mike104]

2.2L non-interference engine is generally bulletproof.

 

The 2.5 SOHC is better than the DOHC, but unless the seller has good maintenance records (oil changes, Subaru coolant conditioner, timing belt & "while you are in there"stuff) you may want to discount the price to address a future HG repair.

 

If the 2.5 has been overheated it can result in the rod bearings dying shortly after HG replacement.

[idosubaru]

Are these just as good as a 2.2 SOHC?

no.

 

well - depends what you mean by "good".

 

would you like me to buy one of these with a blown motor and install an EJ22 in it for you!?

Edited June 10, 2011 by grossgary

[Mike104]

no.

 

well - depends what you mean by "good".

 

would you like me to buy one of these with a blown motor and install an EJ22 in it for you!?

 

^ that is what I would do.

[987687]

I have a close friend who runs rallycross events with his '99 Legacy GT. I know he has an EJ25 engine (not sure if it's SOHC or not) and he's the original owner and his car went 158K before he had head gasket issues. He had the head gaskets done last year and hasn't had any issues since then.

 

That would be DOHC. My experience with those is that if you don't overheat them, they're very good engines as long as they have good head gaskets. Do them once, do them right, and be done with it.

That goes for pretty much any suby motor.

[danbennett2u]

Will echo what pretty much everybody has said. 2.2l is probably overall the best engine Subaru has made as far as durability goes. That said you seem to be favoring Foresters, and none came with a 2.2 from the factory. The SOHC 2.5l (99 and up in Foresters) still has head gasket issues, but they tend to be external leaks (vs coolant leaking internally into oil and cylinders in the DOHC).

 

If Forester is your focus, I would chose in this order:

 

1) one with a 2.2l swap

2) 2.5l SOHC

2) 2.5l DOHC

[AWDfreak]

As everyone has said, the EJ22 is the one to get if you want bulletproof reliability and minimal worries.

 

The EJ25 will need more attention, thanks to all of them being interference and having timing belts.

 

Here's the thing though, the EJ25 was made because the EJ22 is relatively "weak". So if you are one that prefers more "oomph", get an EJ25 unless you do not want to deal with the potential headaches an EJ25 will bring.

 

 

Now there's the naturally-aspirated SOHC and naturally-aspirated DOHC EJ25s.

 

The SOHC EJ25, in my experience:

* sounds more anemic than the DOHC

* produces MUCH BETTER low-end torque than DOHC, but feels like it runs out of breath once you try to rev it up high

* it doesn't really like to be revved too high.

* it's much easier to live with than the DOHC because of the low-end torque, and doesn't have the major head-gasket issues the DOHC EJ25 does

 

The DOHC EJ25, in my experience:

* sounds "sportier" (I LOVE the sound it makes! ) and more spirited than SOHC

* low-end torque is OK (BAD compared to SOHC EJ25), but it really shines once you start to rev it high, especially near redline

* it is a very rev-happy engine

* because the EJ25D (what the naturally-aspirated DOHC EJ25 is called) has plagued faulty original head gaskets from the factory, it is a very risky choice to get a Subaru with an EJ25D due to the extremely high rate of head gasket failure. However, when one gets the updated Subaru OEM gaskets, your head gaskets will be fine

Edited June 11, 2011 by AWDfreak

[1-3-2-4]

^ I agree with everything said.. I went from a Ej18 from a 95 impreza to a Ej22 from a 95 legacy to a Ej25 from a 97 legacy outback and the whole tone of the engine is deeper.. and I'm really enjoying the extra power I can't remember too much but when I had my 03 Forester XS with the SOHC I do remember the low end being a tad better then the DOHC.

 

most of the time driving around in town I'm already in 4th gear.

 

Now I have to say this and I think it sucks.. and this is coming from me driving the Ej22.. but the extra weight on the flywheel on the EJ25 sucks.. downshifts and coasting will still keep the revs up.. and i don't slow down as fast as i did with the ej22.. having said that I still like it over all.