Ej18 to Ej25 swap

[Diablo9420]

I have a 95 impreza witha ej18 in it and it terribly slow, so im going to get a ej25 to put in it, ik the transmissions and mounts are the ame but im curious what ill need off the 2.5 car, im guessing torque converter wiring harness and ecu, so any help on that front would be good

 

Also i plan on putting new headgaskets and timing belt setup before i put it in my car, what brand of head gasket should i get that will prevent the leakage the stock gaskets get over time?

 

Any other info you can think of would be greatly appreciated

[kjester]

I wouldnt buy fel-pro head gaskets, i like becks

[92_rugby_subie]

For the EJ25 arent people using the MLS updated gasket? Im pretty sure I heard that was best.

[Gloyale]

Match the Torque converter to the trans. You may have to swap you're EJ18 flexplate onto the EJ25

 

ONLY use subaru MLS gaskets. I've seen them for sale packaged by "Stone". Otherwise, I'd get them from the dealer.

[Diablo9420]

So i dont need the wiring harness and ecu from the donar car?

[idosubaru]

Yes you'll need the wiring harness and ECU typically speaking (anything is possible).

 

There are two easier options (with a dark side of course, few things are free):

 

1. Swap in an EJ22, that would be a direct bolt in swap with no wiring/ECU - the EJ18 intake manifold would bolt right on top of any Phase I EJ22 block. the later 97 and 98 models had a few more horsepower. Shave the heads, get some delta cams and the EJ22 isn't all that far from an EJ25 power wise and they're - cheaper, more reliable, the valves are actually adjustable (LOL), easier to work on (plugs, valve covers). Ej25's are hard to find in good shape and expensive (for a lesser motor IMO, not a good value for me but to each his own).

 

2. Bolt your EJ18 heads (cheap route) onto an EJ25 block or get better EJ22 heads (that's what I would do), and bolt the EJ18 intake manifold onto the EJ22 heads which are bolted onto the EJ25 block, again avoiding the wiring/ECU work.

 

You *could* attempt to swap the EJ18 intake stuff onto the EJ25 intake manifold - remove the entire wiring harness, etc and bolt it all onto the EJ25. I've laid them side by side but haven't tried it yet. The throttle bodies are quite different in configuration - the EJ18's look sloppy, i don't like those manifolds they just look "busy".

 

But if you're going through all that effort maybe it's beneficial to have the better controller too, so the wiring might be nice.

 

I've swapped a few EJ22, EJ25 ECu's and ran an EJ18 on EJ22 and EJ25 ECU's - i've never noticed any difference. I'm currently running an EJ18 (well actually it was wrecked today while some friends were driving it) with EJ25 wiring/ECU and it runs perfectly fine, i would expect the other way around to not be that noticeable, if at all, if you were contemplating that.

[Diablo9420]

Well my local junk yard has alot of ej25s that say the motors still good figuring it had the headgasket problem and the owner junked it, ive seen a few ej22 but not very mant, the only reason i wanna do the swap is to piss off, my little brother, he just got an integra and thinks its the ************ so i was jus got drop in a ej25 and blow it on him, but if i can easily and more affordably hook up a ej22 then ill jus go search for that, thanks for the advice, how hard is the ej22 swap?

[idosubaru]

how hard is the ej22 swap?

you're asking a question i just answered in my last reply? EJ22 swap is 10x easier than the swap you were originally asking about - no wiring work at all.

 

can you do an engine swap? swapping in an EJ22 is exactly the same as just simply replacing your Ej18 with another EJ18 - you just pull the old out and install the new engine. the EJ18 intake bolts on top of the EJ22.

 

there are only two things to know:

 

1. get an EJ22 with EGR to simplify things since the EJ18 has EGR valve.

 

2. 90-95 EJ22's are dual port exhaust heads and will bolt right up to the EJ18 headers. But they are lower horsepower than later model EJ22's (95 manual trans EJ22's won't have EGR though).

 

96-98 EJ22's are single port exhausts but a few more horsepower - all you need to do is also grab the exhaust y-pipe. It bolts right up the car and has to be removed from the engine to do the swap anyway so it's hardly any extra work.

 

You could also bolt the EJ18 heads onto an EJ22 block and thereby retain the dual port exhaust. I'm not sure if the EJ22 heads flow better or have larger valves/better cam profiles though, i'd probably want the EJ22 heads.

 

personally i'd get a 97 or 98 EJ22 with EGR (most of them have it) and the exhaust manifold (ypipe) to go with it. It all bolts up and plugs and plays.

 

Bolt your EJ18 timing belt tensioner bracket and tensioner onto whatever engine you get if it has the newer style (one piece) tensioners. they are less reliable and show up around 97 models. the older style on your Ej18 is more reliable and you can simply swap brackets and tensioners between old and new style. Unless of course the new engine already has the old style tensioner on it, then just leave it, they are the same parts.

 

you can wikipedia things to see horsepower numbers - later 97 EJ22's have the higher output...but are also interference so you should be installing a complete timing belt kit (belt, pulleys, etc).

 

the problem with junkyard EJ25's is you have no idea how much they've been overheated. could be a great score....or there's a high probability too of lower end bearing failure.

[Diablo9420]

Ik u said it was easier i was just wondering the details, do i need just the y-pipe or do i need the manifolds too? Yes i can do a motor swap, havent done one on a subaru but looks easy enough, and the swap definatly sounds easy enough, hopefully i can find a ej22 and i was trying not to get an interference one but i planed on putting a new timing kit on w.e motor i get just so i dont have to worry about it in th future, thanks for the help

Edited March 27, 2012 by Diablo9420

[idosubaru]

great - you're golden. what you need:

 

1. matching y-pipe for 96+ EJ22's (prior years have dual port exhaust that will bolt right up to the EJ18). the y-pipe is the exhaust manifold, it's all one part and easily swaps out with the other one, just remove and install - it'll make sense when you see it - really simple.

 

2. get one with EGR

 

done - plug and play!

 

if you install a new kit with pulleys and tensioner you'll be golden.

 

for EJ22's:

90-96 are non-interference (though i have heard of interferring 96's, it's rare)

97 and 98 are interference.

[Diablo9420]

Ok is a ebay mizumoto timiming kit fine? I dont wanna sink to much into it cuz its a rus bucket, just to shut my bro up lol, and another question if i can get my hands on a wrx or ej22t will it be easy to drop in? Cuz if i can find a better condition body with 5speed tranny ill drop the motor later on in ther and turbo it, i dont want much with the car i have, but if i can find a clean one ill hook it up

[92_rugby_subie]

Search Mizumoto on here... they have a few review threads I believe.

 

If its a rust bucket, dont turbo it, youre just asking for things to fall apart

[Diablo9420]

Well the turbo question was more for if i find another subaru

[Diablo9420]

Ok so i have a quick question, im a few weeks from gettin my transplant, and i was curious if i wanted to do a 2.5 with 2.2 heads since i have to use the 2.2 intake could i jus keep the 1.8 intake and run my wireharness and it all run properly? I may be a little ahead of myself but im just curious

[idosubaru]

i have to use the 2.2 intake could i jus keep the 1.8 intake and run my wireharness and it all run properly? I may be a little ahead of myself but im just curious

exactly, you got it. the whole point of the EJ22 swap is that you *don't* use the Ej22 manifold because the EJ18 intake bolts right to it. it avoids all the wiring, ECU swapping/issues.

 

so you bolt EJ18 or EJ22 heads to either an EJ18, EJ22, or EJ25 and you're good to go.

 

turbo requires swapping all the wiring, ECU, exhaust, and the engine crossmember as well. it's much more involved swap.

 

EJ22 and EJ25 blocks have knock sensors where EJ18's don't (or all the ones i've seen don't, i'm not sure if maybe some later models may have them). either way, just remove it, it's not used.

[Diablo9420]

Great thanks so now i can jus go find a franken motor post and learn how to do that more correctly lol

[GeneralDisorder]

EJ18's don't have knock sensors - you are going to want the EJ22 or EJ25 ECU with knock control and then add the wiring and sensor for it.

 

The frankenmotor needs knock control in a big way - being high compression it needs the help that much more.

 

GD