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'96 OBS
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Discussion Starter #1
This has been about year in the making, but I have a terrible track record for completing projects so I didn't really want to share much until it looked like I had a good chance of getting it at least somewhat working. Well, about 9 months later than I planned that day has arrived.

As of earlier today I now have the EJ204 out of a 2003 (BL/BP) Legacy 2.0R running well enough to drive around in my 1996 OBS.
Here's a photo from "the good side" (where you can't see the giant rats nest of wires):


Engine management is provided by an open source engine management project called "Speeduino." Here's my totally hacked together testing setup:


Here's a video of (totally not) the very first start:
Raiding the Subaru parts bin: 2003 JDM EJ204 in a 1996 Impreza - YouTube
Yeah, that's a lot more like the 31st start.

You'll have to forgive me for starting in the middle. I'll fill in more of the back story on this as I have time to type it up, clean up the wiring diagrams and dig up old photos. For right now, I just wanted to share my results. I'm happy to answer questions.
 

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'96 OBS
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Discussion Starter #3 (Edited)
Thanks for the interest! I just read the first 4 pages of your journal and holy crap I thought I was stubborn. I didn't know what I was going to do if the JDM engine I bought didn't start. If it dies now, at least I know my wiring and engine management setup is (almost) right and I can "just drop in" another.

Here's what's done so far:
- "190ps" 11.5:1 CR EJ204 out of a 2003/2004 JDM Legacy 2.0R (in quotes because I'm still running the 96 MAF intake and stock exhaust w/ original cats)
- Speeduino engine management (Totally reversible, wired in with two adapter harnesses: one from the engine to the bulkhead harness, one from the bulkhead harness to the 96-98 style ECU connector)
- 3.9:1 5spd out of a 2001 JDM Legacy (2nd gear should top out around 60mph :3 )
- Exedy KSB04 clutch
- ACT Streetlite flywheel
- PowerStop WRX calipers/pads/drilled+slotted rotors
- Facelift hood/headlights/grille. Depo clear corners.
- 10 years of "keep it on the road" maintenance
 

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'96 OBS
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235 Posts
Discussion Starter #5
Ahahaha. Yeah, the wiring is suboptimal right now for sure. I need to clean it up, but I also want to do things like hook up the purge control solenoid valve so I can make the evap system work, hook up the cam triggers so I don't have to run it in "wasted spark" mode on COPs and eventually I want the AVCS hooked up and activated as well for that midrange torque. After a year of weekends working on this thing though, I *just* *wanted* *it* *running*. No AC or power steering right now either and honestly I'm not sure I'll ever get put them back on. The AC never worked in this car since I bought it in 2007 and running without power steering is not nearly as bad as I thought it would be.
 

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needs more cowbell
95L, 07 2.5i, R6
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So it's the avcs dohc version then? Are you going to get the avcs up to get its full potential? Why did you decide on not using a jdm ecu and just adding wires for avcs and dbw? I wonder if there is a model in the year range of those engines, that doesn't have immobilizer.

If it indeed makes that kind of power, would be a good upgrade for the sohc versions like the one in my 07. I swapped in a 2012 sohc from a super low mileage legacy, but if anything ever happens, I may do some swap things instead. My car is already dbw and maybe I could find a way to run avcs.
 

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'96 OBS
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Discussion Starter #7 (Edited)
This actually gets back to the planning stage of the whole swap. There's very little English language info on the JDM EJ204 that I was able to dig up. EU and Russia got a downrated version (lower CR and ~165hp) but even that doesn't seem to get a lot of love. So, basically, I liked the engine, I figured I'd be pretty happy with 180-190hp with lots of revs but most of what I could find about it was mechanical info from jp-carparts.com (i.e., what part numbers it shared with other EJ20s).

So, why not go with a JDM ECU?
1) I couldn't find any EJ204s being sold with a matching ECU and I did not feel like chasing CELs on a CANbus ECU anyways.
2) I couldn't find any front cuts (even if I had someplace to put one)
3) I really had no interest in doing a whole-car harness merge: I don't love wiring and I hate taking interior stuff apart and the goal was for the car to be "down" for as little time as possible (ha!)

1 & 2 still stand. 3 is kind of debatable. The car ended up down for about 3 months in the end. I possibly could have found someplace to keep a front cut if I tried harder. Hindsight is 20/20.

AVCS and DBW:

I definitely intend to get AVCS going eventually to get that mid rage torque but really, the car feels pretty good without it. Except for right off idle and in the places where my non-existent tuning skillz are really letting it down it feels stronger than the EJ22E it replaced in every part of the torque curve. Up past 5000RPMs it just wants to pull. I haven't been pushing it much past that point because I'm finding that I have no idea what I'm doing tuning ignition advance and I'd like to not kill it prematurely. Also, with the COPs running in wasted spark mode, they're effectively at double duty cycle. Not a good recipe for longevity if I'm zinging it out to 7100RPM all the time.

On the technical side, as far as I understand AVCS fully retards the cam advance angle by redline, so I should have the same peak hp give or take. with or without it. Peak torque is probably slightly reduced and shifted to a higher RPM.

As for DBW. I would have really liked to run DBW but yeah, without the JDM ECU or a more expensive standalone it wasn't in the cards. I'll write a little blurb on my workaround and shove it in a different post so I can link to it.
 

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'96 OBS
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Discussion Starter #8
TL;DR #1: You can run a DBC throttle body on a DBW manifold as long as you believe.

I'll be writing up some blurbs about how I got around some of the challenges I made for myself. Here's #1 on the DBW to DBC "adapter" I "made".

I knew going into this that the DBW throttle wouldn't work with the Speeduino and the DBC throttle body wouldn't fit on the DBW manifold. To work around that, I had a plan A and a plan B.
Plan B was to get another N/A phase II intake manifold, move all the necessary wiring over to it and drop it on. That manifold is sitting in my garage right now.
Plan A was to see how hard it would be to make an adapter plate that would bolt into the intake manifold and provide studs to mount a DBC throttle body.. Then I'd just find someplace to put a throttle cable anchor bracket. This was of course easier said than done for my (previously) non-existent fabrication skills.

By all rights I should have gone with plan B, but the same stubborness that got me through this project just wouldn't let me give up on that pretty EJ204 intake manifold and put an ugly EJ222 manifold on.

I'll write up the adapter plate in more detail at some point, but the short version is this:
- The DBW throttle body is much more compact than *any* Subaru DBC throttle body as far as I can tell. This means that the fine folks at Fuji Heavy Industries packed stuff around it in pretty close proximity. Test fitting an EJ18E or EJ22E or EJ222 TB in their intended orientation meant they were running into the fixture for purge control solenoid valve for the evap system, which I'm intending to use. Even if I wasn't though, the throttle cable would have been scraping across the plenum on the EJ204. Because of that, mounting the TB at a 15-45 degree angle only made things worse. Flipping it 180 degrees didn't help either (I can't remember what it was running into).
- Then I found out that if you rotate a DBC TB 90 degrees it will actually *just* bolt into the bolt holes for a DBW throttle body. And in that orientation the throttle cable will *just* clear the top of the plenum.
- So I made a prototype "adapter" plate that just has 4 bolt holes, a hole the same size as the throttle opening and a vertical tab to mount the throttle cable anchor bracket on. That is currently on the car.
- The current prototype "adapter" is made of plastic and the throttle cable anchor bracket is made of angle brackets from the hardware store for mounting shelfs. You can scream now if you want, but it'll be replaced with one made of CNC'ed aluminum before I take it on a roadtrip or idle it in hot weather.
- If anyone working at Lowes is reading this: I would love a sponsorship for this project. Get in touch. :)
- Just to anticipate one more question: I'm running the car off the MAP sensor, not the MAF so I'm not *as* worried about unmetered air sneaking in around the TB. The stock intake is there temporarily because I had it on hand. See above: I have so much left to do.

If you take a look in this slightly older photo you can get a better view of the visible part of the "adapter". Seems like I didn't take any photos of it outside the car. This is probably iteration 10 or so with the first several mockups made in MDF to gauge fitment and then some prototypes in plastic that didn't quite work out for various reasons.
.
 

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'96 OBS
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Discussion Starter #9 (Edited)
EDIT: Now with working image links.

Progress! Actually, *lots* of progress. I got the Speeduino off the carboard box it's been living on for just about the last year or so and stuffed into the stock ECU case. I need to make a new lid for it (since some of the components stick out the top), but it looks a lot less hokey already:


Emboldened by my success I wrapped up the adapter wiring harness I made:


Tuning has been going ... better than I expected it to. I honestly half expected I'd find a way to break it just trying to make it run, but it still seems happy. I'm 100% sure I'm leaving power on the table between not running the AVCS, running wasted spark/batch fuel and not wanting to push the timing too hard, but I'm tweaking one thing at a time. Idle AFR is now close to 14.5 or so. Low load cruise is into the high 13s but freeway cruise is still hovering around the mid 12s. An economy car it is not.

That's the negatives. The positive: This thing *moves* when you put the hammer down above about 4000RPM and it keeps moving right up past 7100. With the 3.9 final drive I can merge onto the freeway in 2nd at 7xxxRPM. 3rd gear tops out high enough to get me sent straight to jail in pretty much any state in the country.

In terms of next steps, I have some mundane stuff that needs to be attended to.
- The ECU needs to get tucked out of the way of the my passenger's feet to avert potential disaster. Long term I want to design and 3D print a new top for it with some room for the extra height of the board. Short term the whole thing (ECU, case and all) is probably going in a tupperware and getting shoved back under the carpet.

- I need to find out why the front right wheel wants to hop accelerating out of sharp turns and give me a bunch of steering wheel wobble when I hit bumpy sections of freeway


The next actually interesting thing to do will be to get some experienced help tuning timing so I can get a bit of the potential power in the lower rev range. I have a feeling my timing is really conservative right now, but I have no knock sensor. :S After that I need to hook an oscope up to the hall effect (?) cam sensors, figure out which trigger pattern they are and get them setup in the Speeduino so I can run sequential/non-wasted spark COP. That should help fueling a tiny bit, but mostly be less of a burden on my COPs, which are right now firing twice as many times per rev as they're designed to.

Next post: My temporary gauge cluster setup.
 

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'96 OBS
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Discussion Starter #11
Well, I just got back from road tripping it 700 miles or so around the Olympic peninsula with my wife. In terms of the engine it's been pretty darn close to flawless mechanically. I'm still working on the tune and learning as I go, but I can live with that.

Unfortunately, the steering wheel wobble is still there and seems worst right around 58mph or so, then goes away around 62mph and comes back in the high 60s. It's on brand new tires and the wheels should have been rebalanced. I'm going to get a shop to look at one of the axle seals anyways so maybe they'll spot something else while they're at it. I'm planning to replace pretty much the entire front suspension anyways (springs,struts, roll center adjusters) so one way or another it'll get solved eventually.

Immediately before leaving (and I mean immediately) I threw on some kartboy front endlinks to replace the absolutely ragged ones from the factory. I literally put them on, test drove it once around the block and then headed out on the trip. :) The rears will go on this weekend probably, but the rear endlink bushings are in much less dire shape.

Also before I left, I finally hacked up a lid for the ECU and got it tucked away under the kick panel:


The lid is made from some 16ga steel plate from the local Lowes (Hey Lowes! Great sponsorship opporunity here) that I hand bent with some C clamps on a palette. It looked really good until I tried to get it screwed onto the ECU case and found it it wasn't nearly as straight as I thought. The gap between the top of the case and the lid is on purpose to provide clearance for some the ECU components (mosfets) that stick up higher than the top of the stock case.

And finally, here's a sight that hasn't been seen on this car for over a year:

Kick panel on and carpet ready to be flipped back into place! (One of my wife's conditions for taking my car on the road trip was that she didn't want to have to worry about accidentally stepping on the ECU the whole time. Totally fair. :) )
 

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Discussion Starter #12 (Edited)
The parts fairy was very kind and in return for only a few teeth (and a couple hundred bucks) I now have these fine pieces of JDM-only goodness:

Bonus tip to anyone who actually reads my journal: When I ordered the bumper cover, my Subaru dealer said there were 3 total left in the US. Now there are 2 (or less). If you want a V1/2/3/4 bumper new-in-box now is probably the time. (Apparently there are like 17 of the lightweight bumper beams. Not a ton, but still might be worth grabbing)

I also had a chance to take a quick hack job at the WRX muffler I had in storage and get it mounted:

I followed this thread: https://www.rs25.com/forums/f5/t119920-another-alternative-running-gd-exhaust-gc-gm.html
I ended up not having quite enough material to work with so I ended up leaving the "secondary" holes I drilled smaller and just running smaller bolts. Hopefully the gasket is lined up well enough. If not I'll deal with it later.
It sounds really, really close to stock inside the car. It's actually most noticeable at partial throttle. At high RPMs I can't hear the exhaust over the engine/intake noise. It'll probably stay on until i have the inclination to do headers, high flow cat(s) and a catback all at once. At least it doesn't drone.
 

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Discussion Starter #13 (Edited)
Today was funtimes(tm). I took the car to a friend's house. He was kind of enough to loan me his garage and help me wrench on it. I'll be helping him work on his 3rd gen Prelude later (and probably cursing at the FWD engine bay) but today he earned at least that. We set out to do:
- Struts all around
- steering rack and outer tie rods
- ... and ball joints


The rack was a little bit of a PITA since we kept doing things slightly in the wrong order but it's in and looking good. Front struts were cake even though I convinced us to line up the whiteline camber/caster strut tops wrong the first time. Where did we get stuck? Ball joints of course. I was set to give up for the night and come back the next day with some tactical nuclear weapons. But, while I was screwing around getting some interior out so we could get to the rear strut tops he hulked out one of the old ball joints with a channel locks and the other one with a punch and sledge hammer.


Tomorrow we'll get the front all buttoned up and swap out the rear struts real quick (... and jinxed it). Then I'll get it aligned Monday and see how P11Ls and AGXs suit me after 12 years (!) of factory stock OBS suspension. Will report back. :D


Sooooon...
 

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You're gonna love the new suspension. I figured I'd never really care for handling upgrades, but honestly they MIGHT be even more fun than power upgrades. Unfortunately, it's like a disease, next you'll need wider wheels and tires, thicker sway bars...
:projectsti.com:

Oh by the way, this thread is full of win! I may have to consult with you in the future regarding this speeduino stuff...
 

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'96 OBS
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Discussion Starter #16
You're gonna love the new suspension. I figured I'd never really care for handling upgrades, but honestly they MIGHT be even more fun than power upgrades. Unfortunately, it's like a disease, next you'll need wider wheels and tires, thicker sway bars...
:projectsti.com:

Oh by the way, this thread is full of win! I may have to consult with you in the future regarding this speeduino stuff...

Oh, I've been planning this exact setup for like a year. I've had the P11Ls sitting in a box outside my bedroom since last October or so T_T. I just never quite had the money saved up for the rest and then ended up doing the engine first because the old one seemed like it was on the way out.


As for the Speeduino stuff: I'm thinking about doing a writeup of what my current setup looks like in a new thread if there's interest. Trying to write it up journal-style would be like a novel and would mostly consist of "And then I did the wrong thing 9 times and the right thing once".
 

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Discussion Starter #17
Gonna be a whole different car. Can't wait to see where it settles.

Keep up the good work.

I got to see it on the ground briefly today. It looks really good, but I bet it's actually going to settle like another half an inch after driving it around a bit. I'm not after the ride height so much as the handling, so I'm happy either way.


Unfortunately, it's back on jack stands tonight because when I went to test drive it I found out that I had gotten the steering u-joint on backwards and it wasn't fully seated onto the steering rack splines. We flipped it the right right way but it still doesn't seem to want to seat far enough to get the bolt on so now I'm at a bit of a loss. We called it quits at ~10PM so It's in my friend's garage overnight. I'll run over after work and hopefully before then I'll do some research and figure out WhyTF that u-joint doesn't want to seat all the way onto the new rack's splines. I will be somewhat cranky if I got sent the wrong rack, but everything else bolts up just fine. I assume it's some dumb thing I did, as that's usually a solid bet. Concentrating at work is going to be pain tomorrow :|
 

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Discussion Starter #18
Update time!

The steering universal joint is in and I'll take a couple minutes to hopefully save some future folks some pain:
1. It is possible to put the u-join in backwards (upside down?) and it will almost seem like it could work that way. Spoilers: It won't.
2. If you just swapped the u-joint and your steering wheel wants to skip or jump but kinda still steers the car, you may have put the u-joint in wrong. Do not drive the car like this. Stop and fix it. You can probably fix this from the top if you're not someplace where you can jack up the car, but it won't be fun.
3. If for some reason you need to get the u-joint off without removing the steering rack, you can loosen the 4 steering rack bolts a bit so it came move around a bit. Then push forward on the rack's input shaft from under the car to get the rack to rotate a bit. That should give you enough slack in the u-joint to get it popped off.
4. Even if you have the u-joint on the right way it can still be a pain to get the two bolts that go through it to start threading. On the steering wheel side, this should be pretty straightforward. On the steering rack side, this can be a giant PITA if you've never done it before. Clean up the splines on the rack and clean out the u-joing then slide the u-joint on by hand. Unless the rack or joint is rusty or damaged it should seat as far as it needs to by hand. If you're having trouble getting the bolt through try backing the joint off by a millimeter or two. Try and push the bolt through while also wiiggling the joint around a bit. If you think you need to hammer the joint on to get the bolt through, you might already have the joint on further than it needs to be.

With that PSA out of the way, here's the car back in my driveway!


Just installed:
- KYB AGX struts
- P11L springs with bump stops and dust boots (Thanks for making this happen 2pot!)
- Whiteline adjustable camber/caster front strut tops (KCA335)
- 20370AA240 rear strut tops. They do seem different/harder than the stock OBS ones, but I have no good way to test for sure.
- Whiteline front roll center adjustment kit (KCA313)
- New stock spring seats/hats/etc (The old ones are somewhere between chiseled spam and hammered shit)
- Jorgen auto rebuilt steering rack
- Superpro rack bushings



I have an appointment to get it aligned at Northwest Rally Sports on Friday. I'm planning to give them the alignment specs 2pot suggested for the P11L springs. I'll probably also have them get my stupid steering wheel straightened, because I managed to get that crooked during the rack/u-joint madness.

No "real" test drive until then.

In the mean time though I'm working on putting power steering back in. I depowered my leaky old rack as part of the swap, but I don't think it suits this car well. Normal driving was fine. Parking I could live with. But the real kicker was that the steering was heavy enough that I don't think I'd be able to auto-x the car effectively. So I scavenged some early 2000s Legacy hard lines and a reservoir and made myself a bracket so that I can mount the reservoir where the charcoal canister used to be. The bottom part of the bracket mounts to the side of the frame rail and then provides a flat surface for the Legacy reservoir to bolt to.


I am planning to reinstall the evap system, but I need to find a way to trigger the purge control solenoid from the ECU, so it's disconnected for now. When I do reinstall it, the charcoal can will go where the stock horn is and the horn will probably move behind the grille.


The test fit was a success!


Tomorrow night I'll yoink my roommate's car, grab some ATF and give the whole system a proper flush. I'd feel dumb if a bit of metal got into one of the lines or pump while they were lying around my garage and damaged the seals on the brand freakin' new rack, so I'm doing this one by the book (for once). :)
 

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'96 OBS
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Discussion Starter #20
I want to boost that manifold. Big ass TB attached :drool:

It looks great right? I could have saved myself so much trouble if I just swapped on the EJ222 intake I had sitting around, but I just couldn't make myself do it. One note on it: It is tall, like *real* tall. It clears the hood by about half an inch. That bracket for the throttle cable touches the inside of the hood. The linkage on the throttle body and the "ear" on the adapter plate stick up into the scoop.
 
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