Hi, Lots of swap/interchange posts here and other sites to confirm, but the '05 was the last year b4 the i-AVLS heads, so stick with the '99-'05 Ej251/EJ253. You'll want to swap the intake manifold/IM and probably crank and driver's side cam sprockets to the 'new' engine - if not an '05. Also, some had EGR. If yours doesn't that makes it easier - just plug it on the donor heads. Otherwise, you'll need to drill/tap the head or do the bypass and run the EGR back into the PCV system- or you'll get a CEL.

To tell good/bad, check the coolant overflow/reservoir for oil residue = head gaskets, check for HG oil leak at the block/head mating area bottom of engine, if the car has no body damage then likely either the trans or engine are likely bad.

Personally, I wouldn't install any used Subaru engine (ok, maybe a '90-'98 EJ22 - which I just did!) w/out at least changing out the HG, as I consider them a maintenance item.

If you're looking for a temp fix, buy a JDM 2.0 engine cheap(ish). Swap the same stuff as noted above.

 

@wtdash My buddy found a same year donor car that was ready for the JY but the engine has some life left in it. He’s hoping it will last a year in hopes he can save for a rebuild.

I appreciate you posting 👍