126 replies to this topic

[Reuben]

1. Introduction.

This thread has been made to store all the tips, tricks, and how-to's on the Legacy Twin Turbo, to single turbo conversion. The following content is based on my conversion, with some research from various forums, and other people who have done the conversion before me, and since me. This thread is specifically aimed at the B and C revisions of the BG5/BD5 Legacy, that have the EJ20R motor. However this doesn't stop you from gaining a bit of knowledge on the how to's of this conversion. I ask you to please read the entire thread through before getting started too. I will be assuming you will be lifting your engine for this, and assuming you know how. It will make life a whole lot more easy for you. And lastly, this is only a rough guide, with a few pointers in it, not a manual or complete instruction set. Please remember that! If you get stuck, figure it out!

And from hereafter I'll be using "V3/4" to simple refer to Version 3 and 4 WRX's, and STi's, and Foresters with the same engine (EJ20K/EJ20G).

First thing you'll need is a shopping list, expect to pay between $1000 - $2000+ for this, but with luck, that is ALL you'll spend. I've tried to list every last washer and rubber pipe and bottle of fluid, so you don't get any hidden costs, and can run a tight budget. Item's marked with an * are not required, but do make things go a lot easier, or make your engine bay tidier etc. I strongly recommend getting everything on the list, and you will see more about them in the thread.



This list applies to the EJ20R conversion:

A Version 3/4 STi ECU
A turbo. Such as a VF22, 24, 30 etc. From a single turbo Subaru.
Single turbo Coolant supply and return lines. You can make your own
Single turbo Oil return line (rubber pipe)(Buy this new)
Single turbo Oil return line (Metal pipe in block) This will be one hard SoB to find, but you need it. Read stage 3 to find out more. (This pipe, to replace this pipe)
Single turbo exhaust manifold. A 2.5L equal length one works too, and offers better fuel economy. But you won't get that boxer rumble
Up-pipe
Downpipe.
Single turbo gear box cross member. Needed if you get a bolt on DP, not if you make your own downpipe.
Single turbo up-pipe bracket. (the one by the turbo)
Single turbo intercooler Y pipe. Anything from V3/4 and 5/6 will work
If you get an STi intercooler with your y pipe, It must be a V3/4 intercooler, and you need to find a V3/4 intercooler bracket, they are damn hard to find!
Turbo outlet to Y pipe hose (Part of Y-Pipe normally)
*V3/4 Intake manifold, complete. If you do not get a complete one, here is what you'll need for it:
*Idle control valve pipe (metal thing that goes on top of the manifold)
*BOV
*BOV Return line/rockercover breather lines (Don't forget the little rubber hoses that connect it to the rockercovers!)(it's a metal pipe hidden on the underside of the manifold)
V3/4 Turbo Inlet/intake pipe
Crank case breather line (I had to make my own)
*F-Pipe, for the crank case breather
*Right hand fuel rail if you want to do the split fuel rail, more on that later
V3-5 Heater core pipes. These pipes go from the water pump, up the side of the head, across the top of the engine, and up to the clutch housing, made of metal pipes, and joining rubber pipes.
V3-5 Heater core hoses, these go from the pipes by the clutch housing, to the firewall.
2 meters of vac line. You can make do with the leftovers from the TT system however. Budget for this anyway
*Single turbo solenoid bracket (This is so you can replace the BBoD)
*Pressure select solenoid (a 3 port solenoid from a single turbo, this is only to tidy up the wiring, you actually already have one in the BBoD that you can use - but it has a great big plug with like 15 wires.)
Bolts to block off the primary turbo's Oil supply, return and coolant return lines on the left hand head. You can pick these off N/A's are Pick-A-Part!
Gaskets for:
Intake manifold
Throttle body
Exhaust manifold
Turbo/up-pipe
Turbo/downpipe
Coolant
Oil
Oil filter + Sump plug washer


And Budget an extra $200 for crane hire, and tools you don't have etc.

If you wish to do the split fuel rail mod while you're at it (estimated cost, $150), which I recommend you do since the intake manifold will be coming off anyway, all you need is
8 feet of EFI (Electronic Fuel Injection) hose. 8 ft really is just enough.
A few hose clamps (6 should do it, you can reuse the originals for the rest)
2 T sections
A second right hand fuel rail, with luck you picked one up with the intake manifold

Coil pack mod (Recommended!!!):
V3/4 Coil pack (And loom plugs), or one from a BG N/A
V3/4 Leads
V3/4 Ignitor (And loom plugs), or one from a BG N/A
New Loom (as in the actual stuff you put around wires)
Some wire for making new loom coil pack loom


For other models:
For BG5A owners - This list applies to you also, only, you probably need to run a WRX ecu, not an STi ECU.
For BE/BH owners, of the Rev A, B and C variety, you can pretty must use this list too, but the ECU, you instead use a V5 or 6 WRX ecu, NOT AN STi ECU! The STi ECU has trouble dealing with the higher compression, so you either need to run a WRX ECU, an aftermarket ECU, or lower the compression. Also, anything marked as V3/4, instead buy V5/6. So want an STi TMIC, it needs to be V5/6. Intake manifold? V5/6. Turbo intake? V5/6 etc.

For BE/BH Rev D owners... I have no idea. The Rev D is a special beast. It has it's own loom and ECU, and engine. It's internally a phase-3 engine, like in the V7 and up, but on the outside looks much the same as a phase 2. For example, it has the old intake manifold and intercooler setup, yet it runs pink injectors. Theoretically, the mechanical side of things I imagine will be much the same, as in, V5/6 intercooler etc. But I don't know about the intake manifold, and if it has different mounts for the top feed fuel rails etc. It might end up being a curious mix of V5/6 parts, and V7 parts to make it work, and it's largely uncharted territory! Certain members are currently researching the conversion, and I'm sure more information will come to light!

[Reuben]

2. Getting Started.

As mentioned above, I said I'll be assuming you will be lifting the engine for the conversion. You don't actually have to, but it will make life for you a WHOLE lot easier! I'm going to skip how to do it for this thread though. This, mainly cause that's too much writing, and I'll probably forget 90% of what you need to do! If you chose to lift the engine, make sure you have a mate who's done it before to give you a hand, and/or use the service manuals. Also, get yourself a pack of zip lock bags, some tape, and a sharpie to keep all your bolts with their associated part, if it's your first time! It takes a couple before you just KNOW where things go and what they do.

Tool's you'll need, will be a socket wrench (set) with a short and long extension, a 14mm impact socket, a power bar, pliers, spanners etc.. and even a little 12mm ratcheting spanner is a huge help for getting the aircon out.

Once you have bought all the bits you need, Rip into it! You'll need to take your intake manifold off, your downpipes off, exhaust manifold and turbos. up to you which order. You also need to swap the gear box cross member over if you're getting a bolt on downpipe. You'll want to drain your oil, and coolant too.

Engine outskies!



I like to take out the BBoD early on

[Reuben]

3. The conversion part 1.

Now, the conversion can begin. Take off the intake manifold first and foremost, and make some room for working (it has to come off anyway, so deal to it first) Get rid of everything on the left side (passengers side) of the engine that is to do with the primary turbo. This includes brackets, turbo, turbo oil supply and return lines, and coolant supply and return lines. The oil supply is in an odd place behind the cambelt, but you can get to it without taking the cambelt off. Blank the oil return and supply with a bolt, and a bit of gasket glue. put the glue around under the head of the bolt after you're put the bolt in, but before you're tightened it. we don't want bits of silicone blocking the coolant system now do we? At least that was my reasoning. The coolant return is also an easy one to block off with a bolt, but unfortunatelly the oil return is a right old bitch. Some pics of these steps:











Or you can shove a bolt in the pipe here like we did for matts



Once you get off the oil's return line, you have to block the holes. Now I tried doing it with a frost plug. First, I couldn't find any, then when I did, none of them fitted!, I needed a 15.5mm plug. I gave up, and just welded what was left of the return, and put it back in after all that effort to pull it out! the other option is to simply slice the rubber line for it, cram a bolt in like we did for matts, and do it up with a hose clamp. that was too messy and rangi for me though. Give the left head a good look over and see if there's anything else left, I think I coverd it all, it seemed to be pretty damn easy.

Now, onto the primary side. You will need to keep the turbo's oil supply line. The coolant supply you will need to make up, unless you get a turbo from the '98 ish era, such as a VF24 or 22, In which case you can buy a proper line from a dealer. The coolant return line you can make your own as well. BUT, the oil return line in the block, you really should steal one from a single turbo. I imagine that will be the hardest piece to find in the whole conversion! One from ANY single turbo will be fine, just get it from a Pick-A-Part. You will need to take the TT one out, and hammer the new one in. This is because the TT's sticks out the right side and conflicts with the new up-pipe, but the Singles sticks to the left and up:











Once you have the coolant and oil returns sorted... It's time to address the heater core lines! This is a new addition to thread 3.0. It turns out I got lucky with using TT ones, they haven't ruptured yet. But, I've had several reports of others getting worn through in weeks!!! The problem is, the TT heater core hoses both go up and over the top of the clutch housing. When you stick a single turbo intercooler on, the Y-pipe pinches them, and rubs them, and eventually eats through them! You need to put on single turbo pipes that go around to the side of the clutch housing. The problem is, this means you must also get the metal pipes that run all the way down to the water pump. They look like this. The lower left is the twin turbo one, the upper right is single turbo. Note how the single turbo pipe shoots off and out of the way.



time to stick on the exhaust manifold, and up-pipe. Don't forget the heat sheilds. With that in place, on goes the bracket. I recomend you at least get the small one. With none, vibration makes short work of the up-pipe felxijoins! People will try talk you out of it some of these seemingly useless things cause it's too much hassel, but seriously, do the job right first time round and bother with the little things.. Now stick on the turbo! Make sure you got the rubber pipe for the turbo oil return on. There is a pipe from the TT's system you can use (i think its from the secondary BOV) but it's short, and only just fits. I would recommend getting the subaru part for this.



Then on goes the intercooler bracket... Right, so new problems: The up-pipe bracket I found conflicted with the oil supply line. The angle grinder fixed that. Then the intercooler bracket conflicted with the turbo outlet. this is because I got a newer model turbo with an outlet that points towards the back more, The older ones (VF24/23/22 etc) point forward and don't have issues. the angle grinder fixed that too.







Check over the engine and make sure everything engine wise is delt to. Next up is the intake manifold and vacuum system.

[Reuben]

4. The conversion part 2.

Right, now to deal with the intake manifold. Strip the TT manifold of all it has. And you will be doing a split fuel rail while we're at it . Take photo's of how the loom is arranged. Also, if you break this, don't worry. leave the vac lines off it, it's not needed. But leave it plugged in so you don't get a CEL (it's to do with emissions, it goes off to the charcoal cannister)

Split fuel rail mod:
This is a very easy mod, you need:
8 feet of EFI (Electronic Fuel Injection) hose. 8 ft is really just enough. I think you need 9 feet for BE's and BH's as the filter is not in the engine bay
A few hose clamps (6 should do it, you can reuse the originals for the rest)
2 T sections
A second right hand fuel rail, with luck you picked one up with the intake manifold

Now, cut your fuel rails like so:


Now take the injectors out of your old left hand rail, and swap them over. TAKE CARE. Basically, it's a c*nt of a job, and it's easy to brake something. just be patient, and use force.

Bolt both fuel rails onto the intake manifold, and cut your EFI to length. I recommend you arrange them under the BOV return/crank case breathers. it makes things tidy and easy to install. Sorry, no pics of how to arrange it. You'll see what I mean though.





And this is from my third time doing it.





Now put the final length of EFI hose on the 2 T sections, loop it around as you don't know what length the supply and returns should be yet. You'll cut it once the manifold is installed, and the engine is in the car. Mark which line is the fuel supply, this line will be shorter FYI. Once the manifold is on and the engines in the car, don't forget to hook up the vacuum lines on the regulators too. I like to make these equal length.

That's the split rail mod complete. simple huh

Now put everything back together on the new intake manifold. Note: Remeber the crank case breather hose to the turbo intake pipe, the TT one is different, either make one or buy the subaru part. Also, if you're using a V3/4 Intake manifold, you need the TT's throttle cable bracket off the old manifold. Note that the rocker cover breather hoses attach to the same pipe that does the BOV return, instead of going over the top of the manifold like in the TT.

Dont mind matt deciding he wanted the manifold painted silver instead...









Ok, so now we have a complete single turbo intake manifold of some description, and split fuel rail to ensure that Cyl 3 doesn't melt after you inevitibly crank the boost up... Put the sucker back on the engine and ensure you connect everything up, like the crank case breathers and purge control solenoid (that green thing you broke... )

With regards to the engine loom! Another 3.0 addition. Thankfully, EJ20R's, and EJ20K's are extremely similar engines. And it's interesting to note, the single turbo engine loom just plugs straight in! We tested all the pins for matts conversion (as he used a single turbo engine loom, wheres I used the TT engine loom), and it all matches up. The differences are... No ignition 3 and 4. The wires for ignition 1 and 2 are now served by the ignitor, not the ECU. That is, in the TT, at the engine loom, the 4 ignition signals come right from the ECU. In the single, the ecu first talks to the ignitor, then the ignitor talks to the engine loom. What we did, was just add the ignitor into the engine loom. Easy. More on the coil pack conversion later!

Just remember, if you chose to use the V3/4 Single turbo loom, you MUST do the coil pack conversion!

Sweet, that's simple aint it. Engine done and dusted! Hardly any work at all is it . And this coming from a damn n00b ;D
Now give the engine a once over, check everything is in order, all things plugged in, all lines plummed correctly etc. Now you can drop the engine back in, and move on to the next step.

[Reuben]

5. The conversion part 3.

There are a few things to note at this point. You'll be wanting to pop the intercooler back on by now, but just remember this. The line that goes from the water pump to the heater core on a V3/4 runs around the side of the clutch housing, but in the TT's it runs up and over right where the intercooler Y pipe wants to be (would normally go between the two TT intercooler pipes). As mentioned earlier. Don't forget about the O2 sensor either, the TT's one will stretch over and fit behind the turbo just fine, but putting the intercooler back on can stretch the wire, I'm lucky mine didn't tear off... Just give it pleanty of slack turbo side before putting the intercooler back on, and you'll be fine.

Right, onto the Black Box of Dooooom! Oh noes! ... It's actually pretty simple really... Jason showed me the pic below when I had to do it, it's really all I needed. Basically make your solenoid box look like the one below, and you're set. Now, in the shopping list I said to get a "*Single turbo solenoid bracket" and "*Pressure select solenoid". While you don't have to, it just makes the TT conversion that much more complete. The bracket I said to get for obvious cosmetic reasons, the solenoid, just so you can lose the big whore of a plug with a mess of wires coming out of it that you won't using any more. The picture of my end result shows this well (thanks cameron for the wiring on that one). Note, I used a Gen 1 legacy bracket! Any work, the V3/4 ones are shaped different, and sort of, look and flow better. But I like my gen 1 bracket, bit of a homage to papa legacy!





If you don't know how to plumb up the single turbo solenoids, simply get a mate, or someone from clubsub over who has a V3/4, and copy their engine bay. Just hook up all the vac lines like theirs, and you're set. The TT Boost control solenoids are 2-port. Do note some version 4 solenoids are 3 port. I have no idea is the ECU has issues with this, I run aftermarket boost control, as does matt... Anyway, for a 2 port solenoid. On the turbo is a vac hose going direct from outlet to wastegate actuator, with a pill in the line, and a t-section. Leave the pill in, and run a vac line from the T to the BCS. I don't know what port the BCS uses, you'll figure it out. The second port is the bleed, and that goes back to the intake pipe. Then you have a hose off the manifold that goes to the pressure select solenoid, then a little hose from the px sel solenoid to the MAP sensor. Done. SO much easier than the 30 something lines for a TT!

I'll point out now, an oddity with the legacy car loom here. The pin the single turbo ECU uses to talk to the boost control solenoid is indeed the same as the Legacy TT ECU's BCS pin. However, that wee BCS wire doesn't go to the BBoD, it goes to the passenger side fender, where the TT's BCS lies. The wire that talks to the Single turbo BCS is actually a different pin in the Legacy ECU (Exhaust valve duty solenoid, to be exact, the BBoD BCS controls the secondary exhaust valve). How to fix this is in the wiring guide coming up next.

Now that's pretty much it. Put everything back in the engine bay make sure EVERYTHING is plugged in, like radiator fans, starter motor ground wires etc. etc. and put that intercooler on. Another note on the intercooler; If you get a V5/6 one like I did, thinking "it's the same shape and size, it'll fit right in". You're wrong, it doesn't You need a V3/4 intercooler (which I later got), and bracket for it. If you used a new gen turbo, like a VF34, or 39, you'll have to trim some of the long end off of the silicone part of the Y-Pipe to fit it (Short end goes to the turbo). I took about 30mm off mine in the end, and it was still a tight squeeze, but it's entirely possible.

Ta-da, all done. Now the fun part, the ECU wiring.

[Reuben]

6. Wiring.

6.1. ECU.

The reason I said in the beginning, that this thread was for EJ20R legacy's only, is mainly because of this; the ECU wiring. You need only solder 5 wires, and you're done! Auto's have a single plug ECU that isn't compatible with any STi ECU, so you're buggered there. My official line on it is you should have got a bloody manual you pansy! Ha ha ha. I am also unsure on the ECU's for the Manual EJ20H drivers... And BH/BE drivers. But what I have found out is the 4-plug EJ20H's are somewhat compatible with the 4Plug EJ20G's, but have more in common with the 3/4's They are a weird bastard mix. I have posted a pinout for you guy's at the bottom of this thread. BE/BH drivers, V5/6 WRX ECU's for the EJ208's, The wiring is much the same, just ignition or coil pack wiring, BCS pin, but they also have a fuel pump controller you must remove, more on that at a later date. Chrisjunkie has all the info on that for now.

Anyway, the wiring for EJ20R drivers:

Here are your relevant docs. If you compare the links below, you'll quickly find out V3's and 4's Just use a EJ20R loom! All the TT bits are blanks on the V3/4 ECU's.
here's some documents to back everything up
V3/4, Plug B137. Courtesy of http://www.northursalia.com/
V3/4, Plug B136 and B135. Courtesy of http://www.northursalia.com/
Twin turbo 3 plug pinout. Courtesy of UK Twin Turbo Legacy Register

To get at the ECU, it's in the passenger foot well.






(don't mind the sequential controller in this pic, was taken before I singled)



Take the plugs out, and you will see what is shown on the pinouts



Wire A9 (loom) into A10 (ECU). Wire A22 and A23 (loom) into A9 (ECU). Ground B18 (ECU).
Swap A19 with A3 <- makes V3/4 ECU talk to the correct boost control solenoid.

And the not so technical drawing of the above description for us simple minded folk.



It's that easy.

Now do note, the joing of A9 and 10 into A10, and Joing of A22 and 23 into A9... This is what we do to make the factory legacy Ignitor-on-Coil-On-Plug setup run wasted spark. You do not need to do it if you do the following coil pack conversion. I wiried mine as above, and ran like that for nearly 2 years, before doing the coil pack conversion. So it works just fine! and is the cheap and easy alternative to the coil pack conversion

If you don't do the coil pack conversion though... you're a little girly girl. Just sayin... that's all. Real me use HT leads...

6.2. Coil Pack Mod.

Hokay, New to 3.0! I've been asked to do a write up on the coil pack mod, to rid ones self of the coil on plug system, and go to the sexy, cheap, and reliable coil pack system.

Eaaasssyyyy. You will need a Coil pack and leads off any Version 3 or 4 impreza, or N/A BG/BD. A matching 5 pin ignitor, and some additional wires and some actual loom stuff. Refer to the pictures to see what these look like!

For the wiring, I just spliced into the engine loom to get my power and ground, and 2 ignition signals. For the power, I think I just stole the 12v supply that goes to the coil packs, makes enough sense. And for the ground, there's a general ground wire you can tap into. Again, the pictures show which wires I used clearly. Then from there I just made a new branch off from the loom with some wires I had lying around, dedicated to the coil pack and ignitor. It's very strait forward! I think I'll let the pics and wiring diagram do the rest of the work for me.

For those who used the single turbo loom, like matt, It's done in much the same way, but it's slightly easier. For the single turbo loom, all you need to so is add the ignitor in, and ground it. So you cut the 2 wires off to the coil pack. From the ECU goes to the ignitor inputs, the ignitor outputs go back into the engine loom where you cut. Then simply T in a ground, and that part is done. Next, double check that the 2 ecu inputs are matched up to the pins on the ECU, I can't recall if you need to change any at the ECU end. I supect you have to put A22 or 23 into A9 or something like that. It should just work if you have already wired the ECU for coil-on-plug like above.

[Reuben]

7. Epilogue and Notes.

Well. What can I say. It's one of those projects that start out seeming fairly simple... then get very complicated... But once you're done, it actually seemed quite easy... ??? It took me three and a half months to do.. but 3 months of that were taken up by my engine rebuild. The conversion itself, only took one (full time) week! add another day or two on for the engine lift and drop, and ta-da, a 2 week project at max (After posting this up, someone did it in a single weekend, including the engine lift!!). I hope that my shopping list will allow you to gather every last piece you need before even starting.

There's not a whole lot left to do from here. I can't actually remember... Some said beware, the ECU will spit fault codes at you like a monkey on crack, but I did a whole engine rebuild, and conversion at once, and didn't get a single CEL! There's not a whole lot to get wrong!

It really is a fun project, and WELL worth it. Im adding this in a year after doing mine, and I must say, there is NOTHING like single turbo. I now look at TT's with distain almost, I have no idea how I managed to cope with VOD. Having a single turbo really is a joy, it's so so SO much easier to work on, and work with. There is great support for aftermarket engine goodies, since you'll effectively had a V3 STi engine.


Notes:
Newer model turbo's like VF39's have different outlets, that point rearwards, instead of forwards like the 22's and 24's etc. This isn't an issue, it only requires you to trim the turbo-y-pipe hose down. Any turbo from a single turbo subaru will work! Twin scrolls will require a twin scroll oil sump, headers and up-pipe, which could double your conversion cost easily. Some may deem that an acceptable price to pay.

Version 5/6 intercoolers do not fit V3/4 Intake manifolds. Their BOV, or aftermarket BOV flange conflicts with the 3/4's idle control valve. While it is possible to make a custom bracket to fit, it will be a source of pain for you. Also, a switch to either a V3/4 or 5/6 STi intercooler will require you to find a V3/4 Intercooler bracket (yep, V3/4 bracket to fit a V5/6 intercooler). These are hard buggers to find, I ended up driving 150km's (return) to waiuku to get one from the wrecker there, at a cost of $25 (and probably $50 in fuel at todays prices)

On the above intercooler 'drama' as Jase likes to call it (he wanted me to add this one in). It can be solved by simply buying a front mount. Remember that your car, (to anyone behind a counter), is now a Version 3 STi, and any part that can fit a GC8 wrx, will fit your legacy. Jason got a GC8 bolt on FMIC kit for his legacy when he did the conversion, and that was drama free (as far as FMIC kits are concerned anyway). He lost a fog light to it though (it couldn't fit past the GTB's foggie) and he needed a single turbo coolant over flow tank though (easy peasy to get from a pick-a-part). The downside is this can add another grand to the conversion easily.

Prepare to spend exorbitant amounts for seemingly benign parts from wreckers. For example, that little pipe that goes from the turbo intake pipe, to the ICV cost me $45 from a wrecker! Simply cause it was obscure, and he saw that I HAD to get one. It would have been something like $5 from a Pick-a-part, but none had the applicable model WRX's for my conversion at the time. The fact that no V3/4 WRX's/STi's were at any Pick-A-Part in Auckland probably raised the budget of the conversion by a few hundred dollars at least. I wish you luck ever finding one that lasts for more than a few days... I still managed to squeeze through the whole project at under $1500 though. (not including things like oil, tools, and crane hire; that all went under the rebuild budget )

The heater hoses are fine in the TT engine bay, they do work with a single turbo TMIC. But that doesn't stop you finding the line that goes to the water pump from a V3/4, it would make the whole lot go together much more smoothly.
Update: I've heard twice now, of TT heater hoses rubbing through and bursting! I now STRONGLY advised you convert to the single turbo style heater hoses (this requires getting the metal pipes that go all the way to the water pump). Turns out I simply got lucky with mine, and the settled before they burst. They have been working for 3 years in their squished state just fine. I still have the single turbo pipes ready to go on when the time comes though.

The turbo oil return... This could quite possibly be the most annoying thing you'll have to do during the whole project. I was lucky enough that "rex-in" had some old RS heads he wasn't using and couldn't sell, so we stole the return from that. any single turbo subaru will have one, and there'll always be a single turb of some description at a pick-a-part (gen 1 leggy's, and V1/2 wrx's), but getting that thing off while stuck in a pick-a-part wouldn't be a fun job at all!!! (i'm sure there's worse... like anything to do with a TT for example ) Basically just hammer the things base a few times to loosen it up, then hammer it left and right and jimmy it out. It's very easy to break, you saw the picks of the primary side one I tried to take out... Alternately you can heat up the block and try loosen it up like that as ben did to get mine out.

Rage 3" downpipes don't bolt up to factory mid pipes > A rage 3" midpipe from a wrx WILL fit, no matter what the twat behind the counter says (you just need to lengthen it by about 5-10cm's, I did that for a 5er). It pays not to mention it's going on a legacy at all, just lie and pretend it's for your V3 STi au. This applies for EVERYTHING you buy for your engine after the conversion.

If you break the charcoal canister, don't worry, you don't need it. It connects to the purge control solenoid on the intake manifold that you can break very easily too. Besides, it's a waste of vac line hooking it up, because the factory rail it has, is thrown out the with the factory fuel rails! I bitched about doing the right thing and getting obscure brackets for the turbo. This, this is different, it's useless. You will just get to smell petrol fumes every now and then, which I love anyway.

Other model legacy's. If you have a Auto BG/BD. Ha ha, tough, what were you thinking buying a auto GTB... Honestly... If you have a manual with 20H and a 4-plug ECU, you can use an EJ20G ECU, but there's about 10 or 15 wires you need to re-pin. Most wires are fine. If you have a manual BH/BE, (EJ208) Your engine I think is more or less very similar to the V5/6 STi engines. The ECU's have been used, but I can tell you what needs to be done to get it working. I also don't have any pinouts for you.
Update: We have found the compression is higher in the EJ208 than the EJ207, so much higher that detonation is unavoidable. You either need to drop some thicker HG's in, redo your short block, or run an aftermarket ECU with custom tune.


Credits:

Thanks to Jason (FastFour) and Paul (ScoobyDoo) for advice and info on the single conversion. And to the websites I stole the wiring diagrams from.
And a big big thank you to Cameron (Fused) for helping me out and doing most the work , and to Ryan (Boostin) for helping me tare apart the engine, and put it back together! Also to Ben (Rex_in) for the oil drain and help, and to David (Miller) for your help too And to everyone else who helped me at some stage. You are all what make club sub a great place

Also thanks to, Strong For Subaru, and Pick-A-Part For supplying me with the bits and pieces I needed for the conversion. Strong ship nation wide, and now offer discounts to clubsub members, so ask for Nathan or Gerald, tell em Reuben sent yah, and you will receive exceptional service and great discounts! When asking for single turbo parts, for the single conversion, do mention that it's for the single conversion! They have now delt with so many, they pretty much know what you need!

And last but not least, the final product, I only realised now, after 2 years, I had never shown this in the conversion thread... lol...


Matts:









Mine and matts:



Mine:

[Reuben]

Reserved.

Specific stiff for BE/BH's, and BG5A's can live here.

Um, info. Look here to see all the photo's from the conversions
http://s197.photobuc...gle Conversion/

Look here to get wiring diagrams, pinouts, and pics of Chrisjunkies BH conversion
http://car.chriswiggins.co.nz/

Reports are coming in of BH5D's, which i previously thought unconvertible, being mostly similar to V7 STi's, and a good match for single conversions. More on this as certain members look into this.

[Reuben]

More reserved post. Watch this space.

[mattapo]

hey man, been meaning to give ya this for ages, the fuel pump relay for a bh

[spark_38]

This thread is always an interesting read, first time on my iPod touch not so good

After spending 50+ hours working on Ben's TT, incl taking a sick day leave...just to do a motor swap!

I realize this mod prob would have taken the same amount of time and make future motor changes a lot easier. Between all of us we have more than enough parts.... I have 3x spare Ver 3/4 intake manifolds - one complete minus injectors! Not to mention other odd bits and pieces hoarded over the years from stripping down two GF8 wagons: one dereg'd, one written off.

[Reuben]

Sweet, you're all set then!

To those that don't want to do it, that like the idea of tt, want a cruiser etc... All i have to say is it's an easy swap, that removes a metric fucktonne of future headaches, and is greatly rewarding.

[FBSBC5]

Sweet, you're all set then!

To those that don't want to do it, that like the idea of tt, want a cruiser etc... All i have to say is it's an easy swap, that removes a metric fucktonne of future headaches, and is greatly rewarding.

Hey Reuben, Ive put V5 heads on, ICV is different, v5 is 6pin BG/BH is 3, any tips or Ideas how to wire in V5 icv to BG loom

[Drunkenmonkey]

ICV from BG dont fit on V5 manifold?

[Reuben]

Now why would you go do that, 20K heads are juuuuuust fine, it's the shortblocks that are problematic.

If you've swapped heads, that means you've swapped manifolds, so will be running a V5 manifold too, which means ICV integrated into throttle body, and a different TPS... Herp derp, this is why you shouldn't mix versions up!! Silly fool. You're on your own now cause of that You need to find the wiring diagram from a V5/6 impreza, and compare it to that of a BG, and see what the extra wires do, find out voltages etc. etc. If that's all too much, the other option is to chop the V5/6 intake manifold flanges off the manifold, and weld them to the V3/4 manifold...

Or, here's an idea, why don't you use the EJ20R heads, since they are essentially identical to STi heads, (bar shim under vs over), and save yourself the whole headache? I state numerous times in the thread that if you're working with a BG, stick to exclusively V3/4 stuff!

I have the wiring diagrams for a BH, which will be the same as V5, but I don't for BG, it's all N/A stuff for the BG. The ICV's may have the same pins and voltages between USDM N/A and JDM turbo though... May have...

[DCVR]

good write up Rubes

[Oscar]

Believe it or not, I have been looking through this write up to help me with my parallel project. Replacing the secondary oil return is something I wouldn't have thought about or realised till about...when I reach the final stage. And with the information about the wiring means I can use either single or twin wiring with minimal hassle and can even choose between 4 plug AND 3 plug with confidence!

Those pictures are also a REALLY big help.

[Reuben]

You need to wire in a single turbo ECU to run a parallel twin, as it essentially behaves in the same manor as a single turbo. So yeah, you'll will def need to following the wiring info here

Have fun attacking a BG5A loom, you'll want to contact gazzy2000 for details.

[madmike]

Whatever you do.... Good luck...
Unless you love wiring and tracing wiring don't do it!!!!!
I'm in the final stages of a bg/bd5 auto-manual and ST conversion now...
What a mission!!!!

[Oscar]

You need to wire in a single turbo ECU to run a parallel twin, as it essentially behaves in the same manor as a single turbo. So yeah, you'll will def need to following the wiring info here

Have fun attacking a BG5A loom, you'll want to contact gazzy2000 for details.

Which is exactly how I am approaching it! I've got 3 chipped BC5 ECU's.