Subaru Forester Owners Forum banner

1 - 20 of 29 Posts

·
Registered
2004 Forester
Joined
·
23 Posts
Discussion Starter #1
It's been a long while since I laid wrench upon a Suby. Mid 90's or so. Friend of mine in college had an L-series of '80s vintage. Wasn't my first flat-four experience, I'd owned a couple of Beetles prior to that. But it was my last for a while, been mostly working with Mazdas of late. Current daily-driver is a turbocharged '92 Miata.


So what's this then? A 2004 Forester XT? Well, so it was in a rollover and has been pretty much totaled, but that's ok. I wasn't planning on using the body anyway.

Guh?

Well, to be honest, the Forester is a bit large for my tastes. And it's got a bunch of stuff on it that I don't really need. You know, doors, windshield, body... Great for the wife & kids I guess. But I'm actually just interested in the engine. For this:

(Well, crap. Apparently I can't embed images w/ fewer than 15 posts. See attachment.)

The design is still a little rough, but that's basically what we're shooting for in this build. Transmission is from a Porsche 914, engine adapter from KEP, and the plan is to drop the EJ255 from this Forester into the mix.


Plan "A", and the reason I bought a whole car instead of just an engine, was to transplant the whole ECU and wiring harness into the new car. Figured that since this motor is already rated for >200 HP from the factory, the stock electronics would be good enough.

Well, turns out I should have done some better homework before the purchase- who knew that Subaru was so far ahead of the curve from an electronic standpoint?

(Answer: not me.)

Variable cam timing? Check. Tumble-generating thingy? Check. Fuel level sensor connected to the ECU for some reason? Uh, ok. Throttle-by-wire? Wait... really!?


Ok, now I'm starting to realize that I may have gotten in a bit deeper than I'd anticipated. Probably should have stuck to my gut instinct and gone with an OBD-I donor. I mean, I've built and installed at least a dozen Megasquirt ECUs, but they were all in cars that didn't have anything called an "Integration Unit" and where there was a physical connection between the pedal and the throttle.


So, what to do...? I could part everything out and sell it all I suppose. But that puts me back where I started, and my chassis builder is getting itchy to get his hands on the engine so we can finalize the placement of the rear suspension and start actually welding pipes together.


Plan "B", I suppose, would be to ditch all of the stock electronics and just build a Megasquirt to run it. The critical sensors seem pretty straightforward, though I'd probably need to pin down the intake cams to a static advance. Not the end of the world, but it annoys me to think about it.


Am I the first person to find myself in this predicament?
 

Attachments

·
Premium Member
2004 Forester 4EAT
Joined
·
5,462 Posts
A subaru in a rail? That's how I got here. I started the searching/finding process of building one and then drove a forester. The AWD won me over on the first dirt road! It's a great motor, but an even better platform. I do agree that you will probably find it easier to go standalone for ecu though. Oh, and whatever you dont use, sell here. If you feel like extracting the entire harness, I may be interested.

WOW, just looked at your pic, 2 seat, no windshield, long suspension. That thing is gunna be nuts. You won't need to mod this motor at all.
 

·
Administrator
2004 Forester XT Premium 4EAT
Joined
·
29,449 Posts
I'd look into an EG33 from a 92-95 SVX if you want OBD 1. Cheap, plentiful, and good for 230 hp.
 

·
Registered
2004 Forester
Joined
·
23 Posts
Discussion Starter #7
Welcome to the forum... If you decide to sell the engine as a whole PM me.
Well, there's a vote of confidence. :biggrin:


I do agree that you will probably find it easier to go standalone for ecu though. Oh, and whatever you dont use, sell here. If you feel like extracting the entire harness, I may be interested.
Yeah, I've got some reading to do. Through searching around this forum, I did find some very helpful links to the factory service manuals, and they're basically teaching me how utterly wrong I was about how simple this would be. I've worked with OBD-II cars before, but all of them had throttle cables and only one ECU.

I'm still going to take a stab at it. My plan is to start unplugging things one by one to see if I can find a minimalist hardware configuration that will still run. Obviously I'm not getting past the fly-by-wire throttle, but if I can keep the ECU running happily without all the interconnections to things like the fuel tank sensors, the other body computers, etc., then I may choose to run it in that configuration.

If that turns out to be a bust, then we'll be going standalone. The intake cams are bugging me. I'm not really sure if I'll be able to come up with something to control them or if I'll windup having to mechanical lock the pulleys in a midrange setting and just live with it. The new MS3 does support variable cam timing, but it assumes that you only have one intake cam to deal with, not two.

If I wind up going that way, I'll be sure to give y'all first dibs on the harness and other parts. I will need to clip a few connectors off the harness (injectors and coils, crank sensor, etc.)


WOW, just looked at your pic, 2 seat, no windshield, long suspension. That thing is gunna be nuts. You won't need to mod this motor at all.
Heh. Nuts is the general idea for this build. We are going to put a windshield on it (mostly because I don't enjoy being pelted in the face with gravel at 80 mph) but aside from that it's going to be a fairly minimalist build.



I'd look into an EG33 from a 92-95 SVX if you want OBD 1. Cheap, plentiful, and good for 230 hp.
I thought about it, passed up a really good deal on one in fact, but a six cylinder engine is just more length & weight that I don't want to deal with.


Aren't you just making an Ariel Atom?

If you are i'm jealous.
No, of course not. The Ariel Atom is copyrighted, trademarked, patented, and has all sorts of other legal protections affixed to it. (It's also $50,000.)

I'm making something that is in no way at all like an Ariel Atom. :wink:
 

·
Registered
none none
Joined
·
8,844 Posts
If you're going standalone, go with a Vipec or something designed for the FXT/STI motor, a megasquirt won't be the best solution. You could also use the longblock and older electronics. Maybe throw on an older cable throttle body from an earlier WRX or something and combine that with a cheaper standalone.
 

·
Registered
2003 Forester XT 2.0
Joined
·
6 Posts
Hey, Joe......wow! best of luck....
If you still have the windscreen washer bottle cap, I'm definitely interested!!!
 

·
Registered
2004 Forester
Joined
·
23 Posts
Discussion Starter #12
Subaru Atom Bomb?
Ha! I haven't settled on a name for the car yet. I'm leaning towards using the name "Weyland-Yutani", for reasons that will be obvious to sci-fi buffs.

My favorite observation on the project so far came from the ExoCars.net forum:
"Anyone willing to strap 2 or 3 hundred HP to a 1/2 ton vehicle and drive it like you stole it Is in fact a thrill seeker and therefore Type A"
So maybe the "Weyland-Yutani Type A" would be a fitting moniker.



If you're going standalone, go with a Vipec or something designed for the FXT/STI motor, a megasquirt won't be the best solution. You could also use the longblock and older electronics. Maybe throw on an older cable throttle body from an earlier WRX or something and combine that with a cheaper standalone.
Well, I mention the 'Squirt simply because I have a large amount of experience with it. I have built and installed about a dozen of them, including the one that's powering Chris Swearingen's 300 HP nationally competitive SSM-2 Miata. So it's definately where my comfort zone is.

I've done a little bit of looking into the Vipec system. A couple of things are bugging me about it. First, the available documentation seems to be very Impreza-specific, and the pinouts I've found in their documentation don't seem to match the ECU pinout of the Forester. They also seem to assume (quite reasonably) that you're plugging this ECU into a vehicle that hasn't been stripped down to the bare essentials. With the MS, by comparison, you have all the schematics and documentation in-hand, and don't need anything more than a MAP reading, the crank trigger, and a couple of temp sensors to make it run. Granted, I'd be stuck generating basemaps from scratch (the MS doesn't seem to have much caught on on the Sooby universe) but I'm pretty good at that.

These damn intake cams... If it weren't for them, this would be a no-brainer. Does anybody know if I can just nix the whole advance mechanism by installing a cam sprocket from an exhaust cam or an older (non-vvt) engine?



Hey, Joe......wow! best of luck....
If you still have the windscreen washer bottle cap, I'm definitely interested!!!
I'll check when the vehicle arrives. (It's still on a transporter being shipped to me.) If it's there, you can have it for free, less cost of shipping.



Welcome to the forum from Niagara Falls! :bacon:
Ok, somebody's gonna have to help me out here. Why do we have a dancing bacon smiley? :biggrin:
 

·
Registered
2004 Forester
Joined
·
23 Posts
Discussion Starter #14
Yes, I do quite like bacon. I'm just not sure if I'm ready to commit to a serious relationship with bacon yet.



I just wondered it it had some deep meaning. Over at MiataTurbo.net, for instance, we have several smileys that are, shall we say, reflective of certain lifestyle-oriented stereotypes which are commonly held of Miata-driving men. :biggrin:
 

·
Registered
2000 SF5 JDM S/TB 5MT
Joined
·
270 Posts
iv found an AMAZING freeware tuning and ecu modification problem. its called RomRaider.

small download, gives you acess to all of the subarus ecu features. it allows you to turn off the CEL and ignores the warnings at the click of a butten. it has speed limiter removal, allows you to design your own fuel and boost maps. if it goes into limp mode after disconnecting things, open your ecu maps up and turn off the warning for that sensor, then it totally ignores it!!!!

pm me for more info
 

·
Registered
2004 Forester
Joined
·
23 Posts
Discussion Starter #17
Kiwi Fozze, that is a terrific find. I'll have to do some research and see what sensors and devices I can actually live without, and which ones are actually going to be necessary for engine operation. I'm guessing, for instance, that the fuel tank sensors aren't actually required as primary inputs.

I wonder if it could be to run without the electronic throttle system... All of the tables I've looked at so far (I'm viewing the ECU maps for an '05 LGT) seem to use RPM and "load" as their inputs. I'm hoping that load is determined merely by MAF/MAP, and that TPS isn't a factor.

Heck, even if I decide to go standalone, just having access to all the basemaps for fuel and timing will make a terrific starting point.

Gonna have to order me onna them there Tactrix cable thingys. :D

[/*******]
 

·
Registered
2010 Forester Sport-Tech
Joined
·
169 Posts
Sounds like you're building quite the fun-machine!!! [insert jealousy]
Will this be designed for on- or off-road?
Keep us posted with your build, and post photos.

Are far as bacon is concerned, how could you not commit to a serious relationship with bacon, it's SO tasty !!! LOL :bacon::bacon::bacon: Mmmmm.....Baconnnnnn......
 

·
Registered
2004 Forester
Joined
·
23 Posts
Discussion Starter #19 (Edited)
Sounds like you're building quite the fun-machine!!! [insert jealousy]
Will this be designed for on- or off-road?
Keep us posted with your build, and post photos.
Street-legal, on-road. I intend this to be a combo daily-driver / AutoX pwning machine.

I'm currently in the queue behind one other project with the chassis fabricator. Attached the most recent progress shot of the vehicle he's currently building for someone else. Mine is going to be nearly identical to this one, though of course with the EJ255 instead of the type IV VW.

Also: AAAAARGH.

Just got a call from the transport company. My Forester was supposed to be here today, now they're saying Sunday morning. I'd really hoped to have the whole weekend to start digging into the electronics... Ah well.


Are far as bacon is concerned, how could you not commit to a serious relationship with bacon, it's SO tasty !!!
I think bacon & I just need to spend some time apart right now. If it loves me, it'll be waiting.
 

Attachments

·
Registered
2004 Forester
Joined
·
23 Posts
Discussion Starter #20
If you still have the windscreen washer bottle cap, I'm definitely interested!!!
Vehicle arrived this morning. Sadly, the washer bottle is missing.


Progress is being made on the electrical system. I've been going slow and methodical, leaving as much wiring connected and removing the interior around it. Dashboard is out, so far I've conformed that the vehicle runs happily without the instrument cluster or the airbag module.

Planning to hit the Integration Module and the Security Module tomorrow. Found out today while going through the wiring diagrams that there's a Fuel Pump Controller Module. That's going to take some probing to figure out... Why couldn't they have made this simple? :D
 
1 - 20 of 29 Posts
Top