I've done some research, but figured I'd post just to make sure I didn't miss anything.
I'm looking at buying a '90 Legacy parts car, has an EJ22 and FWD auto trans, ridiculously low miles for the price. In my area, there are tons of late 90s Legacies, Outbacks, and Foresters that have headgasket issues. I'm wondering how difficult it will be to swap the old OBD1 EJ22 into an OBD2 car, and if there are any years in particular that are easier or flat-out incompatible.
Here's what I know so far. Please correct me if I'm wrong, or feel free to add anything I've missed:
- I'll need dual-port exhaust manifolds as newer cars are generally single-port.
- I may want to swap flexplates as the Ej25D's is heavier.
- I may need to find an intake from an ODB2 EJ22, and the intake from an ODB2 EJ25 wouldn't fit my EJ22.
- If I use the ODB2 engine harness from the newer car, I'll need to steal a few sensors from the OBD2 engine.
- The ECU from my '90 Legacy *should* plug in to the OBD2 harness, but the car might run fine with the OBD2 ECU, even if it's from an EJ25D.
- I can't just plug the ODB1 EJ22 engine harness into the ODB2 car's main harness.
- I could swap over my entire ODB1 harness into the newer car and forego ODB2 compatibility. My state doesn't do inspections so I don't have to worry about that.
- I want a car no newer than '99 as the EJ251/Ej252/EJ253/Ej254 are going to be a ton of work to swap from, or not even compatible at all.