Ok, so I think I'm in over my head, got an 07 impreza standard 2.5 with 5 speed. The motor and wiring harness were removed to install regular turbo motor. Bad investment? Problem I incountered right off the bat was the wiring harness, after getting all the info here is what I'm left to figure out.

The new motor and wiring harness the car came with is from a 2004 base turbo impreza with an automatic trans and I need to put this into a 2007 Impreza non-turbo 5 speed.  What will make this work? Do I need the harness out of a 07 turbo with standard trans to make this work/ or is this much more complicated than that?

04 would be cable operated throttle body, and 07 would be drive by wire, or DBW.

 

Yes, you'd need a DBW harness, but these are not like the old imprezas or GLs, the 05+ ECU is CANbus and talks to the TCM, BCM and antitheft.

 

If that isn't enough, you'd need the ECU, TCU and harness from the 07 as well, as with the keys and antitheft module so the system will be happy. Otherwise, you're not going anywhere.

 

Have you checked for crossmember clearance? I know the GC8 and the GG imprezas need a crossmember swap to a turbo crossmember.

 

And a clutch? You've got a pull style, yeah? You'll need an 06+ WRX clutch to match the 5 speed you have, plus an EJ20 flywheel.

 

 

Did you score big on this 04 WRX motor? Cause the easiest thing is to just go buy a turbo car..

04 would be cable operated throttle body, and 07 would be drive by wire, or DBW.

 

Yes, you'd need a DBW harness, but these are not like the old imprezas or GLs, the 05+ ECU is CANbus and talks to the TCM, BCM and antitheft.

 

If that isn't enough, you'd need the ECU, TCU and harness from the 07 as well, as with the keys and antitheft module so the system will be happy. Otherwise, you're not going anywhere.

 

Have you checked for crossmember clearance? I know the GC8 and the GG imprezas need a crossmember swap to a turbo crossmember.

 

And a clutch? You've got a pull style, yeah? You'll need an 06+ WRX clutch to match the 5 speed you have, plus an EJ20 flywheel.

 

 

Did you score big on this 04 WRX motor? Cause the easiest thing is to just go buy a turbo car..

 

My 07 WRX is not canbus, it did not start until 08 for the Impreza. You are correct about the DBW and clutch tho..  And he would need matching immobilizer parts.

 

The only way this swap could be feasible is if you have the entire body harness from the 04 or a complete stand alone engine management/custom harness. This swap would not be legal in most states.

My 07 WRX is not canbus, it did not start until 08 for the Impreza. You are correct about the DBW and clutch tho..  And he would need matching immobilizer parts.

 

The only way this swap could be feasible is if you have the entire body harness from the 04 or a complete stand alone engine management/custom harness. This swap would not be legal in most states.

I was not 100% about the WRXs... I know my 05 9-2x (Impreza wagon) was (but it was NA). I figured it would be with the immoblizer/anti-theft system would be integrated at that point (since the STi has it..)

You sure the 2005 9-2x was canbus? The legacy/forester/outback/tribeca started canbus in 2007, the Impreza range (wrx/sti/2.5i) did not start canbus until 2008. If it was, that is news to me.

Thanks for some ideas and here is where it's at.

New crossmember, flywheel and clutch. The motor is bolted in ready for ???  here's what I'm thinking and could use some more input. Can I put the electrical engine harness from an 07 WRX onto the 04 engine or did some of the sensors change? I came across an 07 WRX body harness already so if the harness will work on the 04 engine I should be almost there.

 Once I have all the wiring hooked up can't I just get the ecu reprogrammed??

And yes, next time turbo to start with, although I probably learned quite a bit more about the car doing it this way.