engine question

[99soobiegt]

ok so this is probably a wicked stupid thing to ask but i wanna make sure, anyways if my legacy has the ej25 and i find impreza parts from a 2.5 impreza can i use the same motor stuff i.e. pistons, valves, retainers, rods, etc? and the reason im asking this is becuz through some research ive found that its hard to find parts specifially for the bd/bg legacies like motor wise and when i have come across parts they seem to cost a damn arm and leg lol im wrong please correct me and if im not then id assume it just made my engine hassle that much easier

[chuckthefuk]

All DOHC 2.5 liter engines found in the 97-99 legacy's are called EJ25D or "Phase 1"
Only the 98' 2.5RS & 98' Foresters used the EJ25D.

If I am not mistaken you can use any short block from any subaru as long as your sensors are swapped over and wired in properly. You can even use a EJ257 STi short block with forged internals and your DOHC N/A heads if you wanted to. Although its a bit bullet-proof for the $$..

Oh heres a quote from Pat Olsen
"The EJ25D is the DOHC EJ25 which was used in the 2.5GT and Legacy Outback from '97-99, and in the 2.5RS and Forester in '98. The EJ25D is commonly referred to as the "Phase 1" EJ25. (There was also a DOHC EJ25 in the 2.5GT and Outback in '96, but it was not the same engine. I'm not sure what its designation is.)

The SOHC EJ25 has been used in all the Subarus since '99 or '00. I think we're up to the EJ253 now, but I could be wrong. The SOHC EJ25s are the "Phase 2" engines. The EJ251 to EJ253 are all variations on the same thing, just adding new features and tweaks along the way. I think if you go searching online at www.subaruparts.com (http://www.subaruparts.com) or one of those sorts of sites you'll find that the Phase 2 shortblock has remained the same from '99 to at least '05.

The engine wiring harnesses and associated plugs are not the same on the DOHC and SOHC engines, so you can't put a SOHC engine into a DOHC car (or vice versa) and just plug 'n' play.

The ECU plugs are vastly different, so you can't put a DOHC ECU into a SOHC car (or vice versa) unless you completely re-do the harness.

Pat Olsen"

hey chuck, whats the difference between an ej25d and ej25de?

[chuckthefuk]

From what I have seen its a JDM engine code. No EGR valve.
-Chuck (tapatalk)

[Airgne]

Import performance parts has engine kits for subaru.

[ouch1011]

I'm not totally sure if you could use the EJ25D heads on a EJ257 because the AVCS changes a lot of things on the heads, which I would imagine changes some oil passages on the block. You would be better off getting the EJ257 long block if that were the route you wanted to go.

And I'd hardly call a box stock EJ257 "bullet-proof." The pistons are pretty weak, lots of people break ring lands with barely over stock power, especially the later model nes.

[99soobiegt]

thanks guys! ill check out that import performance parts and keep doing some research but im glad to know that 98+ RS's have the same motor cuz finding parts shouldnt be that hard i would imagine

[Grafton]

I'm not totally sure if you could use the EJ25D heads on a EJ257 because the AVCS changes a lot of things on the heads, which I would imagine changes some oil passages on the block. You would be better off getting the EJ257 long block if that were the route you wanted to go.

And I'd hardly call a box stock EJ257 "bullet-proof." The pistons are pretty weak, lots of people break ring lands with barely over stock power, especially the later model nes.

the oil passages should be the same between the head and block on all ej series engine

[mike-tracy]

the oil passages should be the same between the head and block on all ej series engine

https://sl-i.net/FORUM/images/imported/2010/09/EJ22e20head20gasket-1.jpg

22T block with 22E HG's.

coolant passages aren't ideally matched, but on open deck blocks they might be closer.

[Grafton]

thats suprsing the oil feed for the heads matches up but not the coolant, I thought the ej22e & ej22t heads were from an almost identical casting

[99soobiegt]

well if thats for the 2.2 and i have a 2.5 and if i use 98+ impreza rs engine parts do i have to worry about the same thing?

[Grafton]

well if thats for the 2.2 and i have a 2.5 and if i use 98+ impreza rs engine parts do i have to worry about the same thing?
no worries for the 2.5 all the na stuff is open deck just match the headgaskets with the heads

[99soobiegt]

awesome thats good to know that as long as the head gaskets fit that i am all set hopefully ill have the cams and exhaust done soon!! :) thanks guys for all the helpful info!!