I searched but could not find a definitive answer.

 

The car in question is a 1999 Impreza OBS MT with a seized motor due to previous owner driving with oil filter fallen off after a quick lube job.

 

So I'm pondering, in the interest of getting this car back on the road with last $$ spent, can a donor Phase 1 motor (long block, intake, injectors, etc.) be a direct swap for a 99 OBS (originally phase 2)?

 

Is the wiring harness and ECU off the phase 1 motor required?

Thanks

No and the phase I engines are not an upgrade in reliability. That would be a bad idea - mostly because the phase I would require a different manifold that is not compatible with the phase-II harness.

 

GD

Edited February 9, 201115 yr by GeneralDisorder

Dang, thanks for the insight GD.

 

Guess I'll have to keep sourcing for a cost effective used Phase 2 or think about rebuilding the seized motor zzz

One more Q, I noticed that many listings are indicating 00-01 EJ22 (assume they are phase 2) but does not include 99 models. Is 99 a transition year between Ph1 and Ph2?

No - if it's got plugs in the valve covers - it's a phase-II. They only used that engine from '99 to '01 so they are hard to find.

 

You might looking into putting in the EJ253/251 instead - also a phase-II engine but more powerful and larger displacement.

 

GD

Thanks again GD.

 

Keeping with the KISS mindset, is the EJ251 a direct swap? It'll mate up to the EJ22 Ph2 MT and use the same sensors/wiring harness?

Keeping with the KISS mindset, is the EJ251 a direct swap? It'll mate up to the EJ22 Ph2 MT and use the same sensors/wiring harness?

no it's not plug and play (always) but it is easy. bolt EJ25 intake onto the EJ22 (a thing you can't do with older engines but you can here). count the triggers on the sprockets and swap them if they're different. but that's really easy and being inteference you should be installing a new timing belt anyway IMO.

 

you could also bolt your Phase II EJ22 heads onto a Phase I Ej22 block and install that. not sure how bad the drop in compression would be, but it would definitely run.

Let's Frankenmotor the OBS! (1999)

 

So let's say I was to reuse my EJ22 Ph2 heads and toss in a EJ25 short block, which EJ25 variant will bolts up to a 99 5MT (originally with the EJ22 Ph2)?

any EJ25. well, i haven't checked the 2010's yet but i doubt you're looking for that new.