1st Legacy engine swap - ej20e - ej20d

[Guest]

This is my first engine swap, had a 94 legacy ej20 sohc n/a which blew head gasket, so i was advised to put in another engine. So i found a 93 ej20 dohc n/a and and put that in. I used the loom off of my old engine as the new one didn't match up with the plugs in the engine bay (understand that i am trial and error all the way) engine starts but it idles rough - surging like crazy. Do i need a new Ecu for this engine?

[Guest keltik]

What are you using for coils? The SOHC motor would have a coil pack and the DOHC motor would use coil on plug right?

[ReubenH]

We've stuck a SOHC 2L into a 250T once, the engines just swap around fine. I can't recall if there was coil back issues, but either way, just keep what the original car had, and put it on the new engine. But i'm pretty sure DOHC N/A's are coil pack too.

The one to watch out for is injectors. 2L SOHC should be white injectors, 2L DOHC should be red injectors. The red ones are bigger, i'm GUESSING, to keep up with the DOHC heads. When we stuck the SOHC into the 250T, no worries, just stuck the red injectors into the 2L, and kept the 250T ecu. But going the other way, you may have to find a DOHC 2L ECU to drive the red injectors.

Here's another wild guess, but i reckon there would be enough leeway in the whites to cope with the upgrade from SOHC to DOHC. But don't take my word for it, i'm just making s*** up there.

~

I'll take the opportunity to list the various N/A engine/injector combo's i know of here. This is for phase 1 (pre 98) only. No idea about phase 2's

2.0L SOHC = White

2.0L DOHC = Red

2.2L SOHC Dual port (i.e. Normal) = Red

2.2L SOHC single port (Post 96 USDM, i.e. f***ing weird US spec thing) = White

2.5L DOHC = Red

[Guest boostin]

Why not just bolt the 20E manifold to the 20D??

Always try and reuse the old manifold if nothing was wrong with it.

[ReubenH]

Are you sure SOHC bolts to DOHC? Maybe they do, i dunno.

[Guest boostin]

Why wouldn't it? I can't see any reason for it not to.

[Guest]

Unfortunately the sohc manifold doesn't match up with the dohc, bolting different. I will swap the injectors and see how that goes. i was also told to replace the airflow meter so i will give that a go and let you know what happens...fingers crossed.

[ReubenH]

Always simply match the njectors and AFM to your ECU. So if you keep the old ECU, swap in the old injectors and AFM. If you use a DOHC ECU, used the DOHC injectors and AFM.

[Guest boostin]

 Adam said:

Unfortunately the sohc manifold doesn't match up with the dohc, bolting different. I will swap the injectors and see how that goes. i was also told to replace the airflow meter so i will give that a go and let you know what happens...fingers crossed.

True, I had a look at a 20E on Friday. The ports are smaller and the bolt holes closer together as well as offset. Bugger.

[Guest]

both my sohc and dohc have red injectors?? should i still swap them over or will there be no difference?

[ReubenH]

Iiinnnteresting.

No, if they are reds, they are reds. (unless they made post 98 reds, like pre and post 98 yellows?)

What car did the 2.0L SOHC come out of btw? gut a chassis number or lisence plate?

[Guest]

My car is the 1994 Legacy with the SOHC - plate - BJJ186 - vin - JF1BG5KJ4SG008616

The DOHC i am putting comes from a 1993 Legacy - plate - ZR3697

[ReubenH]

Bugger, NZ new eh? I can't decode that vin. How about posting up the details on the vin plate, like applied model, and engine numbers?

But it's a 94, so if it does have reds, should be perfectly fine for the DOHC engine. You maaaaayyyyyyy have to swap the engine loom off the SOHC onto the new engine, if the plugs don't match. But i think that should be all. it should be a fairly straight forward swap hopefully.

I'd say just keep the original ECU, and AFM from the SOHC, and go with that. Take a look and see if the DOHC ECU is a match though.

[GT2.2]

Ok Reviving this old as thread seeing this is the only thing close to what I'm looking after a search.

"Warning: this topic has not been posted in for at least 120 days. Unless you're sure you want to reply, please consider starting a new topic." Yes... yes I am sure I want to post here.

OK so I'm looking at converting my EJ22E to to DOHC (instead of SOHC) at some point in the future and just looking for any info out there. Google has resulted in nothing but USDM SOHC to DOHC turbo builds which are not helpful for my NA. Don't bother with the "buy a turbo" spiel either. I had a turbo once. It had awful fuel economy and liked to viciously attack trees at every opportunity...

Back on topic. I understand the heads themselves will bolt on to the EJ22 with no issues, but what else is generally needed other than the right cam belt kit, tensioners, etc? Car has Red injectors which reading here are what I need anyway - sweet.

Also what is the benefits to going DOHC over SOHC anyway other than the ability to rev it out a little bit more? Slight gains in torque? HP?

[Jakee]

Go DOHC on one side and SOHC on the other. Roll with 3 cams