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2003 Legacy Engine Compatability


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I have a 2003 Legacy Sedan manual trans. with no engine. Trying to figure out what engines are compatible with the car

I should ad I currently have  two motors. An ej22 phase 2 which I think makes it a1999, and a ej25 from 2001 legacy.

Edited by steve56
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EJ22E 2.2L Motors (Phase 2 preferably, but Phase 1 motors will bolt up just a hole on the starter won't line up and I think a transmission hole doesn't line up)

 

EJ25 (think the D, 1, and maybe the 2) 2.5l motors

 

EJ20

 

I think most, if not all of the EJ motors that are '96 or newer should work.  

Edited by lstevens76
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Anything from before 99 and some 99s will not work without a lot of modification. The blocks are compatible but not heads etc. are not

 

Look for 2000-2004 Legacy, Forester and outback are the easy ones. They were single overhead cam EJ25 motors. I think there was a subtle difference between 2000 and 2001 and the 2002-2004 but it was an easy difference to overcome. Do a search on here or someone with more first hand knowledge may chime in. I am not sure what year the Impreza went to Phase2 but there are some EJ22s that are compatible with your car as well.

Edited by AdventureSubaru
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Anything from before 99 and some 99s will not work without a lot of modification. The blocks are compatible but not heads etc. are not

 

Look for 2000-2004 Legacy, Forester and outback are the easy ones. They were single overhead cam EJ25 motors. I think there was a subtle difference between 2000 and 2001 and the 2002-2004 but it was an easy difference to overcome. Do a search on here or someone with more first hand knowledge may chime in. I am not sure what year the Impreza went to Phase2 but there are some EJ22s that are compatible with your car as well.

 

What do the heads have to do with wether a Phase 1 "complete engine" will work or not?  He would just need one from an Automatic w/ EGR on it.  

 

The 2003 Legacy shipped with an EJ25 engine Phase II.  If he drops one of those in there is nothing he/she has to change.

 

On the EJ22 I believe the engine harness would have to be swapped and might possibly need an intake from an EJ25 off an equivalent year donor car.  

 

It has nothing to do with the Block or Heads, but simple electronics.

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The heads are the difference and are incompatible because of the intake manifold and associated electronics. In 99 they switched to phase 2 and sensors, Throttle body, injectors, wiring all changed. The bolt pattern for the intake manifolds are not compatible. So the car needs the sensors etc. which needs the phase 2 intake manifold, which needs the phase 2 heads.

 

Seen a few people wrongfully assume that the early EJ motors would work and waste a lot of time and money in the process. In theory it could be done with a lot of fab work - adapter plate to bolt a phase 1 intake manifold to phase 2 heads etc. or if one were inclined to rewire the car with phase 1 electronics wiring and ECU like the guys do when they EJ an EA car.

 

But the logistical nightmare always says the same thing - get a phase 2 motor that's actually compatible so you can drive your car.

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The ECU for a phase 2 motor will run a Phase 1, it's been done. The same the other way as well (phase 1 ECU running a phase 2).

 

As you mentioned sensors the Engine wiring harness will plug in. As I mentioned he would probably need to swap the harness.

 

Why do I know this? Because I've spent the last few days figuring out if a Phase 2 would work on my OBS. I found a lot of people who have swapped in a phase 1 into a phase 2 car, but not as many the other way around. But I have learned it can be done if I have the harness.

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On an EJ25 SOHC engine, 2 things MUST match the original engine or it will not start.

The crank sprocket must match the original engine.

The left cam sprocket must match also.

In addition, whether it has EGR, single or dual port heads.

Otherwise, what Adventure said. 

 

Just because "it's been done" doesn't mean it was done right.

 

To answer Steve56, the '01 Legacy (if you can either match or swap the crank and cam sprockets) should work just fine with no other modification or dickering.  The fun part is figuring out which set up was in the car originally.  Even for SOA, using a VIN to get this info is only right about 50% of the time.

 

ps: if you get an engine from an automatic, make sure to add the timing belt guard on the oil pump.  You may have to switch out the oil pump to be able to do this. 

 

How much, if anything, do you have of the original engine?

 

Emily

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I don't have anything from the original engine except most of the bolts from removing engine. My 01 ej25 is from an automatic. So I know I need a fly wheel. So i guess I need to pick up a crank sprocket and cam sprocket from 03 ej25 also.

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