2004 EJ25 conversion questions

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eddbmxdude
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2004 EJ25 conversion questions

Post by eddbmxdude »

Hi everyone,

Firstly, apologies for yet another Subaru to T25 conversion question thread. I've done loads of Googling, searches on here and read every page of the RJES website back-to-front and upside-down but still can't find the answers to a couple of questions I have.

My brother and I are converting our DG1.9 to Scooby power and have bought a 2004 Legacy Estate with a SOHC EJ2.5. We spent most of yesterday stripping the engine and loom out of the Scooby and I noticed a couple of things as we were doing it which has left me with a few questions. I've done a few engine conversions on other cars before, but nothing this modern or complicated electronically.

Our Legacy doesn't have a throttle cable. There is what looks like a servo on the throttle body with an electrical connector going into it. I haven't actually started stripping out the dash loom yet, so haven't looked, but I assume there is a potentiometer on the throttle pedal of the Subaru which I'll have to somehow fit to the van and a part of the loom will run up to the pedal instead of a mechanical cable? Anyone else running this type of throttle arrangement in a van?

The Subaru has two cats and two lambda probes. Will I need to keep the cats and probes? If not, I'm planning on keeping the standard Scooby manifold and fabricating a short bend to connect to the standard backbox of the van. I've read a lot of things about exhausts and how complicated/expensive they are on Subaru conversions but the flange on the Subaru manifold looks to be roughly in the right place to just have a 180 degree bend and run a long backbox across the rear of the van like the standard setup. Our van isn't lowered and sits high anyway because it's a Caravelle, so I'm not too worried about ground clearance.

Any answers and advice greatly appreciated. I'm planning on getting the conversion parts and sending my loom to RJES.

Cheers,
Edd
1989 1.9 DG

multisi
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Re: 2004 EJ25 conversion questions

Post by multisi »

The throttle set up changed in 2004 to drive by wire , you need to keep and use the Subaru pedal and wiring and make the Subaru pedal set up fit your van. There is info on the internet from conversions in the usa, search drive by wire Subaru engine vanagon and photos and info comes up, vanaru and benplace are names that look like they have done these later engine conversions. The exhaust sensors are needed for the ecu to work aswell as the immobiliser. I only have experience with early 90 s Subaru engines which are the easiest to install, one of mine doesn't even have an exhaust sensor as standard .
1992 red lle 2.2 subaru 1990 rhd caravelle 2.2 subaru 1986 california import vanagon

eddbmxdude
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Re: 2004 EJ25 conversion questions

Post by eddbmxdude »

Thanks for the reply!

It's amazing what you find when you're searching for the right thing :D I wasn't searching for drive-by-wire which is why I wasn't finding any info. I'll have a read through the wealth of information I've just found.

Thanks!
1989 1.9 DG

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syncroandy
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Re: 2004 EJ25 conversion questions

Post by syncroandy »

Hi, I've not been on the forum recently so missed this until a mate pointed it out.

I've done a fair number of Subaru harness conversions for EJ20, EJ22, EJ25, both non-turbo and turbo. The latest EJ25 job I've done was from a 2003 Legacy 3rd gen (BE9), which had pre and post-cat Lambdas and EGR. These were all retained in the conversion to keep the ECU happy, as was the factory-fit cruise control. Components from the donor required for the electrics to work (aside from the ECU) are just the immo unit (about 2" x3") and the ignition barrel with the immo transponder coil.

AFAIK, in the EU market at least, 4th gen Legacies (BLx) have a completely different Canbus-based drive-by-wire electrical system. The immo is inside the dash panel. Based on what I've read and a quick scan through the wiring diagram, in addition to the ECU, dash panel, ignition barrel & pedal sender, a central control module known as the 'body integrated unit' is also required for the Canbus ECU to function. Additionally, some Canbus signals from other sources (eg. ABS ?) must be spoofed to keep the ECU happy, and there is a commercial device to do this, from Subarugears. So the complexity, cost (and chances of the engine not working 100%) are *significantly greater* with the 4th gen electrics than with the 3rd gen electrics. Plus the installation would be compromised (in my opinion) by having the additional components to hide away somewhere.

I'm aware that in the States folk are using 2004> engines, but last time I looked which was admittedly quite a while back, I couldn't find much useful information on how they're solving the electrics problem. I was left with the impression that US-model electrical systems may be different and easier to convert than EU-model electrics. Or, that folk in the US simply are prepared to spend a lot more on their conversions, and/or are prepared to accept more compromises.

If you do find a viable solution to this, please post up about it here as I'd like to know !
Syncrosport
Volkswagen Transporter, reloaded.

252 GC5 EJ25 AAN L90D
246 097 AFN AVL+ L90D
Syncronaut #004

eddbmxdude
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Re: 2004 EJ25 conversion questions

Post by eddbmxdude »

Thanks for your reply Andy. Although, I'm not sure I'm liking the sound of it :(

Having to spoof all those signals sounds like a real pain. Just took a look at the Subarugears website. $800 for the canbus emulator :shock: :shock: :shock:
I'll keep searching, we've stripped the car down and got the engine and all the loom out now, so if we have to abandon it at this stage it'd be a total pain in the a***!
1989 1.9 DG

tazzboyxx
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Re: 2004 EJ25 conversion questions

Post by tazzboyxx »

I have a can-bus subaru in the back of my westy, it can be done but is a lot of work over the older units!
Anything post Sept 2003 (2004MY) will be a canbus system.

Quick run down-

You need the dash binnacle, BIU (Body integrated unit), key, immobiliser ring and ECU. The immobiliser ring reads the key, message to BIU which then sends a message to the binnacle to confirm which then sends a message to the ECU to continue running. All via canbus. BIU also sends other info to the ECU, some you can fake, some you just have to put up with an error message (One error is when you put the lights on, dash shows a error as i don't know what ohm or volt the BIU is expecting so it thinks a bulb has gone somewhere. Clears when you restart)

Can't use RJES reversed coolant manifold as the outlets and sensors don't make it possible.

Drive by wire throttle

Circa 18 wires front to back with 3 shielded canbus lines.

Speed sensor (I have a subarugears gearbox so use the feed from that) i use the subarugears canbus box already noted. If you know anyone that has any skills with Arduino or the like you can build one yourself and use the standard hall sensor.

You'll need to do the loom yourself, i couldn't find anyone to touch it, here or the US. Too limited a market to make commercial sense which i understood so ready yourself for a fair few hours of sticky fingers!

I have a copy of the Subaru workshop manual which includes the full wiring that you're welcome to have. You're also welcome to come and see mine if you're ever near ludlow.

eddbmxdude
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Re: 2004 EJ25 conversion questions

Post by eddbmxdude »

Thanks so much for your reply Tazzboyxx. I feel a little more confident.

When you say dash binnacle, do you mean the dash clocks? I've got the whole loom including the full dash loom sitting in a box in my living room, so I should have everything I need.
Not being able to have the RJES reversed coolant manifold is a bit of a shame but doesn't really make much difference to me.

It would be great to come and have a look at yours sometime, especially the wiring. The wiring is the bit I'm least confident about, so that's one thing I'll struggle with if I have to do it myself I think. Glad to hear there's a way around spending $800 on that small box. I think I'll look into that more and see if I can find someone who knows their way around an Arduino.

8)
1989 1.9 DG

tazzboyxx
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Re: 2004 EJ25 conversion questions

Post by tazzboyxx »

Yep, dash clocks. I decided to use mine rather than have it rattling around, reason why i have so many wires front to back.

Luckily i didn't pay anywhere near $800, i have an early development model. They are a nice piece of kit though but with the early UK canbus models you don't get all the functionality that's designed into it.

If you PM me i'll email over the workshop manual, you can see what fun is ahead!

Welcome over anytime.

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