'79 Brat EJ22 Retrofit Build Thread

[mka]

Hey all - my last old project subie didn't work out so hot for me, ended up having to sell due to various circumstances after getting her running again - lost steam when she needed an AC repair that was just a pain to chase.

Recently though I've jumped back in with both feet (up to my neck, it would seem) and I bought a '79 Brat with the original intent of breathing life back into the EA71 that was in it, however that would appear not to be in the cards for me. The freeze plugs popped when the little truck was parked (probably back in 1997), and with the water in the heads and valve gallery the studs have all but rusted the heads to the block permanently (as far as I can manage, anyway. I've included a photo of my skookum in this regard - someone may have some tricks and better luck pulling her apart and rebuilding than I but after a week of every penetrating oil mix, mallet, block of wood, and sledgehammer in my garage I have put that aside.) During my initial attempt to revive the old car I also found how hard it was to get critical components like front strut assemblies, 4x140 wheels, etc. It seems these parts are just getting harder and harder to source, and the ones I found on the used market were a bit of a gamble at best, so I Bought a '97 Impreza OBS with an EJ22 and 5 speed to swap in.

I'm hoping this build thread will help keep me somewhat accountable and also give me some motivation to document what I'm doing. I've always been in awe of folks who can put together a build thread or repair thread start to finish and have found a number of them extremely helpful in the past on other projects - perhaps if I detail what I'm doing here it'll keep me on track and give back in a way, as what I have in mind is no small task. I've only seen it done one or two other places that still have the photos and details available, and not in detail on this particular vintage of subaru, at least not to completion.

Anyways, enough blabbing on from me and onto the broad strokes of the project:

Take my 1979 Brat husk, and replace as much as is possible of the underlying driveline with the components out of the 1997 Impreza wagon while keeping the outward aesthetic of the old truck.

I've seen swaps like this completed on Gen 2 Brats, both with the entire driveline swap and just an EJ swap with an adapter plate. I intend to follow the former path as the original EA71 transmission would be short lived with the new engine, and since i'll be replacing a lot of the suspension components matching things up I would imagine will be easier.

Current state as of this intial post -

Brat:

interior is mostly gutted, still need to remove and recondition the dash and get a sense of the condition of the underlying components. Engine is out, but still need to pull the transmission and test fit the EJ. Expecting based on all the other Gen 1 swap documentation I've got my hands on to have to notch the frame pretty good to get clearance, and probably some significant transmission tunnel work too.

Impreza:

Interior is also mostly gutted, ECU is removed and in safe storage inside. Removed the dashboard, heater box and AC componentry. One good more push and I should be able to have the EJ wiring harness out to begin thinning that out. I'm considering attempting to retrofit the OBS A/C system into the Brat, but I have to look at the mechanics of how that might work and whether or not I'll have the real estate.

 

Anyways, wish me luck - I really hope I don't make an rump roast of myself with this one 😅

[mka]

Got the main bulk of the wiring harness pulled out this afternoon - It's pretty freeing to be able to just yank stuff out without worrying about "will it go back in where it came from and look good." (after labelling connections, anyway)

 

Still finalizing exactly what I'm going to keep vs what I'm going to abandon - but right now planning on transplanting most of the Impreza harness into the Brat body and adapting at the terminations where needed, especially since I'm not sure of the condition of the original wiring.

I'm also even more heavily leaning toward retrofitting in the impreza HVAC unit and lower center console trims. Taking a good imaginative sit in the gutted cab of the Brat holding the trims and HVAC parts up to the available space has me nearly convinced this is possible, especially since I also plan on transplanting the trans tunnel from the Impreza where that console and handbrake mounts up.

 

So far so good. Still a scary prospect of a project but even only at this point, I'm still learning a lot.

Edited December 15 by mka

[mka]

Small hiccup, probably the first of many. I've got a neighbor who has appointed themselves the code compliance patrol and as a result a letter from the city regarding the new donor husk. Vehicles in the open need to be registered and "Appear operable." Gotta give the neighbor credit, they work fast. Brought the donor home on the 11th, and the report is dated the 12th. Not even a full 24 hours. Some people, am I right?

Operation "put good roller tires on the brat" is the new name of the game, and operation "fast track the impreza stripdown" is shortly behind it. With rollers on the brat I should be able to rearrange the shop a little to let me push it in and out as I work on it. Gonna need to get it in there anyways at some point to start the fabrication work, so silver linings I guess.

 

[573417h]

hi MKA, is a car cover an option, as this will get around the "being in the open" part, i suspect your neighbour doesn't appreciate the current eyesore lol -regardless of what it might turn into. 

[mka]

Good suggestion - I'm ahead of you with the car cover and had it purchased the day I brought the donor home. It is now underneath said cover and I'll be turning it around to face the house so the missing hood isn't so apparent. I'm in full agreement that it's an eyesore, I'm just surprised at the quickness of the neighbor though perhaps I shouldn't be, our municipality provides a live app to report with now. Whether it is enough to satisfy the city, well, we will see. I suspect between the cover and having one of these in the shop at most times should be sufficient to keep everyone off my case long enough to cut what I need off the donor husk and send it to scrap.

Regardless, I've got inflated roller tires on both vehicles and the cover on the donor now. Going to clear some space in the garage/shop to push things in and out so I can start fabricating. Picked up the final major piece to the puzzle for a while yesterday as well - a relatively fresh 5 speed cable transmission - the only major part the donor didn't have.

 

[mka]

Code compliance issue is no longer - gave the compliance officer a call and he was extremely easy to work with. Donor husk is in the garage for the time being, but apparently a car cover will suffice if I need to move it back out into the drive.

That out of the way, we got the first test fitting of the EJ out of the way yesterday. It would appear that with only a slight extension of the mounting slots on the original crossmember, the new engine should drop right into it, but as expected the fit is very, very tight. It could (by my measurements anyway) be done without notching the frame, however that would leave mere millimeters of clearance at the back of the valve covers. It will still be a much tighter fit than its original chassis even with notching, so like past builders I will also be notching the frame. (Noted where I'm notching things out in blue sharpie in the photo.) I should have about a half inch of clearance on either side when that's complete unless I find a way to relocate that forward mounting bolt for the subframe - in which case I can probably get a little more.

I also have 99% of the original wiring harness out of the donor now, and I'm pretty decided on attempting a full retrofit of most of the newer components into the old car, including the HVAC system. By my eye everything *should* fit, but it will be extremely tight.

Since I'm also going as far as installing pretty much everything else of note from the impreza, I'm also considering either adapting the power steering rack to fit the old Brat crossmember, or adapting the Impreza crossmember to fit the Brat, although I suspect the simplest route would be to ditch the power steering in its entirety and just use the original Brat steering gear. My only concern there would be replacement of components on the steering gear down the line - I hate having to track down parts for weeks or months at a time.

These next few days I'll be pulling the old 4 speed from the Brat and starting on the frame notching job. Somewhere in there I'm also going to do a refresh on the EJ while it's accessible. Oil pump, rear main seal, timing kit, that kind of thing, but that will likely be after the new year holiday, especially since I forsee a lot of removal and reinstall of the new engine and transmission while i do the fabrication on the crossmember, firewall, and transmission tunnel to get those to fit where they need to be.

 

PS - as i build on this I'll be putting the parts and pieces I no longer need up for sale, including the complete but now partially disassembled EA71 engine. Maybe someone with more patience or skill can get that head free and give this thing a new life. Same goes with the transmission and other miscellaneous components as I go.

 

Edited 52 minutes ago by mka