what do i need to swap a wrx engine into a bc legacy

[benny]

hey people around the world im new to this kind of stuff. i have a bc legacy and want to stick a wrx engine into it. do i need gear box and final drive from the same model wrx. i will need the ecu and engine loom from the same model wrx . what else. also this is a non turbo legacy. please help. first build

[kimokalihi]

You will need basically everything under the hood. And I mean everything. You're gonna need the full harness from the engine to the ECU. I would go ahead and swap the entire dash in because you'll want the gauges to go along with your new OBD2 ECU. You'll need all the turbo related sensors and wiring. The whole engine. I don't think you'll need the transmission or differential. Crossmember from WRX to clear exhaust manifold. Radiator from WRX to fit with the plumbing of your turbo engine.

That covers most of the stuff but I'm sure there's a few other items I haven't thought of. It's a HUGE job you're about to tackle and very few people have done it. Most people just swap in a JDM EJ20G which is OBD1 and easier to swap with only adding a couple wires to your ECU. If I was going to do that swap I would only do it with an STI engine and only the USDM one. And then you'd need the stronger 6MT STI trans and that's a ton of money.

I have an EJ20G swap in my turbo legacy which had all the necessary sensors and wiring required already but it was still nowhere near easy. What you're thinking of doing is twice as hard but there's plenty of people here or on NASIOC that can help you through it.

[Legacy777]

Welcome to the BBS.

Personally, I would not recommend you go with a WRX swap unless you've tackled similar swaps before. As kimo mentioned, there is A LOT of stuff that needs to be swapped over. The big challenge is the ECU. The location of the ECU is completely different, the wiring is completely different, there are additional sensors that need to be added, even for the fuel system in the tank. It's just a very monumental task to undertake without a complete understanding of what the WRX ECU is going to need sensor wise to work properly.

I would also suggest an EJ20G swap. That's probably going to be one of the easier options and you can run the EJ20G ECU without really having to completely re-wire the car. There are a few additional wires that need to be added, but it's much more manageable in comparison to the WRX swap.

[wtdash]

You don't state your location or what vintage WRX you're referring to. If you're looking @ current gen stuff, not going to be an easy swap.

But +1 on the EJ20G swap - way easier and search on here for 'rob tuned' ej20G. You'll have more power much easier than trying to put new into old.

GL,
Td