Legacy 2.2 5 speed into 2.5 swap

[slaytalera]

Im concidering doing a 5 speed swap on my outback, which is a 2.5 auto, with a trans from a 2.2 legacy of the same year. Do i need to worry about an ECU swap? anything i need to know before i jump on it?(ill be getting the whole car, so ill have everything).

[chuckthefuk]

Your EJ22E ECU will run the EJ25D with a lower output fuel map. Not a big deal but its a little under powered but not by much.

There are other issues like the starter and such but nothing that will cause delays.
-Chuck

[slaytalera]

I guess i cant just run the 2.5 ECU since its designed for auto?

[chuckthefuk]

I am not 100% sure you may need to ground out certain pins to trick it into thinking its not AUTO anymore. There is a thread somewhere on the forum that talks about the AUTO ecu.

-Chuck

[ouch1011]

I am not 100% sure you may need to ground out certain pins to trick it into thinking its not AUTO anymore. There is a thread somewhere on the forum that talks about the AUTO ecu.

-Chuck

The auto and manual PCM is pretty much the same. It should run fine with the auto PCM as long as you move the pin from the TCU diagnostic pin to the AT/MT identifier pin and ground it. There is more info on here...

Like many Subarus, the PCMs are pretty interchangable. I'm actually running a PCM from a 98 RS 5MT (the only one available with the EJ25D) and it runs it great.

BTW you'll probably need to swap the rear differential as well, since your OB should have a 4.11 FD and the 2.2 Legacy should have a 3.9.