Ej conversion donor questions
- T'subaru
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Ej conversion donor questions
Hi all,
I just picked up an ej20t for my rx. Can someone please plumb me up on potential donor cars ? I'm not sure what compatibility issues there are and if the ecu is trans or turbo specific, as well as the harness. Time to revisit some excellent conversion threads.
Thanks, Mark
I just picked up an ej20t for my rx. Can someone please plumb me up on potential donor cars ? I'm not sure what compatibility issues there are and if the ecu is trans or turbo specific, as well as the harness. Time to revisit some excellent conversion threads.
Thanks, Mark
conversion
If its going into an rx, go get yourself a decent fuel pump, swirl pot and rewire the fuel pump circuit. Use a wrx gearbox and diffs, custom one piece tail-shaft. Use an aftermarket computer (Vi-Pec comes to mind) run a cooler with GOOD PIPING!! from there the rest depends on weather you are offroading or onroading it. If u need cooler pics ect i have some floating around but my engine is out at the moment getting some new bits, and possibly going into a brumby in front of a GTR diff and sigma gearbox RWD HERE I COME!!
Cheers, Allan
Cheers, Allan
- T'subaru
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At this time I plan on using an adaptor plate for my conversion. I'm curious about what years/models used the ej20t to help in my hunt for an ecu and harness. Sounds like other items are necessary too, like fuel pump and cooler. This is where I'm a bit lost as my overall knowledge of subaru's is quite poor........ which is why I hang out here with the smart guys.ORX-18 wrote:If its going into an rx, go get yourself a decent fuel pump, swirl pot and rewire the fuel pump circuit. Use a wrx gearbox and diffs, custom one piece tail-shaft. Use an aftermarket computer (Vi-Pec comes to mind) run a cooler with GOOD PIPING!! from there the rest depends on weather you are offroading or onroading it. If u need cooler pics ect i have some floating around but my engine is out at the moment getting some new bits, and possibly going into a brumby in front of a GTR diff and sigma gearbox RWD HERE I COME!!
Cheers, Allan
EJ20T is not an official designation. It is used for all 2.0L single turbos. So yours could be anywhere from 1993 to 2009. There are a couple of differences in ECU;s and harnesses, but basically 94-98 are all very similar. If you take the oil filler cap off it will have the year of manufacture on it (assuming the cap hasn't been changed). Post up some pics and people might be able to identify it.subuaroodude wrote:At this time I plan on using an adaptor plate for my conversion. I'm curious about what years/models used the ej20t to help in my hunt for an ecu and harness. Sounds like other items are necessary too, like fuel pump and cooler. This is where I'm a bit lost as my overall knowledge of subaru's is quite poor........ which is why I hang out here with the smart guys.
Did you buy it just as a motor or did it come out of a front cut or have a gear box attached ? Can you get the gearbox code or the vin plate will have the engine and box code if you can get hold of it.
- T'subaru
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Its a '93 according to the oil cap. I bought motor only from an importer. They listed engines serial nunber as A779077B. I took a quick look at the engine ( dark here and raining like crazy ) and I'm not sure where they pulled sn from. Heres a couple pics if it helps.niterida wrote:EJ20T is not an official designation. It is used for all 2.0L single turbos. So yours could be anywhere from 1993 to 2009. There are a couple of differences in ECU;s and harnesses, but basically 94-98 are all very similar. If you take the oil filler cap off it will have the year of manufacture on it (assuming the cap hasn't been changed). Post up some pics and people might be able to identify it.
Did you buy it just as a motor or did it come out of a front cut or have a gear box attached ? Can you get the gearbox code or the vin plate will have the engine and box code if you can get hold of it.
Thanks! Mark
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- T'subaru
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Looking thru my receipts they listed model as EJ20DET.niterida wrote:I'm not 100% sure but I think that is an RS motor - there are 2 bolts holding the plug caps on, the WRX's only have 1 (or is it the other way around?)
If its an RS motor it may have noisy lifters which they all end up having. Only real way to fix them is with WRX heads AND pistons.
cheers. Posibly I'm looking for RS Liberty donors?
I have just checked and that is definitely an RS motor. So 93 is probably correct. you need a 94-97 WRX loom and ECU, or 89-93 RS loom and ECU.
There is nothing wrong with RS motors, even if the lifters start rattling it will still keep going OK. It will lose a bit of power but probably nothing you would notice, and it wil lbe noisy but just fit a loud exhaust and crank the stereo
And you have to move the knock sensor or it will think it is pinging and go into limp mode.
There is nothing wrong with RS motors, even if the lifters start rattling it will still keep going OK. It will lose a bit of power but probably nothing you would notice, and it wil lbe noisy but just fit a loud exhaust and crank the stereo

And you have to move the knock sensor or it will think it is pinging and go into limp mode.
- T'subaru
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subuaroodude wrote:Maybe a subi dealer can take me from an engine sn to model number and models used in.
cheers
I'm doubting the importers knowledge at this point. They also have listed this as an EJ20DT, which I have found tech info on line for '02 thru '05 engines.niterida wrote:EJ20DET doesn't exist - DET is a Nissan designation isn't it ?. Officially it will be EJ20K I think, (there is K, G, R etc but hardly anyone uses those anyway).
- T'subaru
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Cool, must the donor be an ej20t? Can I use same years if its an EJ22T? Is ecu transmission specific as I will retain my d/r ea82T 5 speed. Lifter noise..no worries as I have a sound system that kicks a--niterida wrote:I have just checked and that is definitely an RS motor. So 93 is probably correct. you need a 94-97 WRX loom and ECU, or 89-93 RS loom and ECU.
There is nothing wrong with RS motors, even if the lifters start rattling it will still keep going OK. It will lose a bit of power but probably nothing you would notice, and it wil lbe noisy but just fit a loud exhaust and crank the stereo
And you have to move the knock sensor or it will think it is pinging and go into limp mode.

Don't need to worry about finding what it came from - it is an RS (or Legacy GT in Japan) and ran in Liberty's from 89-93.
Yes you need to find an RS or GT loom and ECU. If you find a GT make sure it is Gen 1 not a Gen 2 (which are twin turbo), also I think you need to make sure it is not an automatic loom as they are totally different AFAIK.
Yes you need to find an RS or GT loom and ECU. If you find a GT make sure it is Gen 1 not a Gen 2 (which are twin turbo), also I think you need to make sure it is not an automatic loom as they are totally different AFAIK.
- T'subaru
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Thank you Niterida, your help is greatly appreciated!niterida wrote:Don't need to worry about finding what it came from - it is an RS (or Legacy GT in Japan) and ran in Liberty's from 89-93.
Yes you need to find an RS or GT loom and ECU. If you find a GT make sure it is Gen 1 not a Gen 2 (which are twin turbo), also I think you need to make sure it is not an automatic loom as they are totally different AFAIK.
Cheers, mark
- El_Freddo
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A donor vehicle is what comes with everything you need in general. Really all you're after is an EJ20T wiring loom and matching ECU. If possible, grap either the entire intake manifold and its components or the engine's loom and all the assoicated sensors. There may be suttle changes between the engine loom and the rest of the ECU loom. As for the adaptor plate, Andrew T summed it up well in post #6. Shouldn't be too hard to do. Downside is the clutch pressure - you'll probabily want to beef it up while you've got it out...
Other than that the main difficulty of an EJ conversion is the wiring harness. Basically don't cut anything from the motor. Find the ignition wire, permenant power wire, fuel pump wire and back up power wire (I've "plumbed" the back up power and permenant power in together before the fuse). The others to T in are: speed sensor (although apparently not needed, I've connected mine), and I'm sure there's more, but I can't think of the atm I'm sorry.
Good luck on your conversion!
Cheers
Bennie
Other than that the main difficulty of an EJ conversion is the wiring harness. Basically don't cut anything from the motor. Find the ignition wire, permenant power wire, fuel pump wire and back up power wire (I've "plumbed" the back up power and permenant power in together before the fuse). The others to T in are: speed sensor (although apparently not needed, I've connected mine), and I'm sure there's more, but I can't think of the atm I'm sorry.
Good luck on your conversion!
Cheers
Bennie
- T'subaru
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Thanks Bennie, the knowledge here is always appreciated greatly! Here's where I'm going with this. I'm fixing my ea-t to get me thru the winter. Then the RX gets parked and all power and drive train gets transferred to my '90 wagon and the ej20 gets installed with more current ej trans and diff. lsd of course and 5 spd, not sure if low range is needed though as I drive on road and beaches only....what do you think?El_Freddo wrote:A donor vehicle is what comes with everything you need in general. Really all you're after is an EJ20T wiring loom and matching ECU. If possible, grap either the entire intake manifold and its components or the engine's loom and all the assoicated sensors. There may be suttle changes between the engine loom and the rest of the ECU loom. As for the adaptor plate, Andrew T summed it up well in post #6. Shouldn't be too hard to do. Downside is the clutch pressure - you'll probabily want to beef it up while you've got it out...
Other than that the main difficulty of an EJ conversion is the wiring harness. Basically don't cut anything from the motor. Find the ignition wire, permenant power wire, fuel pump wire and back up power wire (I've "plumbed" the back up power and permenant power in together before the fuse). The others to T in are: speed sensor (although apparently not needed, I've connected mine), and I'm sure there's more, but I can't think of the atm I'm sorry.
Good luck on your conversion!
Cheers
Bennie
Cheers, Mark
- El_Freddo
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You probabily don't need low range and I'm not sure that the turbo AWD boxes from the liberty/legacy's came with low range anyway - if you're goint to use the box from an EJ serie subi it might make the choice for you...
If you're going to keep the L's AWD box in the RX (I presume this is for the coupe and it has an AWD box) and you're all for splitting the box it would be well worth the effort to swap the low range to a standard NA L's low range is it is much much better than the standard low range that came in the coupes! That way its your choice if you want to use it or not, plus it'll help out the turbo to spool up nicely when offroad.
I dunno if you'll need the low range for beach driving as I haven't done much sand driving, only once so far and that was this time last year! (good times!). I'm pretty sure we were in high range as we were cruising along a relatively flat beach...
That's about all I can be helpful with at the moment...
Cheers
Bennie
If you're going to keep the L's AWD box in the RX (I presume this is for the coupe and it has an AWD box) and you're all for splitting the box it would be well worth the effort to swap the low range to a standard NA L's low range is it is much much better than the standard low range that came in the coupes! That way its your choice if you want to use it or not, plus it'll help out the turbo to spool up nicely when offroad.
I dunno if you'll need the low range for beach driving as I haven't done much sand driving, only once so far and that was this time last year! (good times!). I'm pretty sure we were in high range as we were cruising along a relatively flat beach...
That's about all I can be helpful with at the moment...
Cheers
Bennie
- T'subaru
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I've eyed the low range swap posts and i'm leaning that way.I have awd w/low and diff lock currently. I just got the rx running last weekendEl_Freddo wrote:You probabily don't need low range and I'm not sure that the turbo AWD boxes from the liberty/legacy's came with low range anyway - if you're goint to use the box from an EJ serie subi it might make the choice for you...
If you're going to keep the L's AWD box in the RX (I presume this is for the coupe and it has an AWD box) and you're all for splitting the box it would be well worth the effort to swap the low range to a standard NA L's low range is it is much much better than the standard low range that came in the coupes! That way its your choice if you want to use it or not, plus it'll help out the turbo to spool up nicely when offroad.
I dunno if you'll need the low range for beach driving as I haven't done much sand driving, only once so far and that was this time last year! (good times!). I'm pretty sure we were in high range as we were cruising along a relatively flat beach...
That's about all I can be helpful with at the moment...
Cheers
Bennie
