Will the 4-speed automatic from the impreza work with the WRX engine? Also do the 2.5i and the WRX have compatible wiring harnesses and ECU's?
uhh..idk. If I were you, I would check out some of the forums. I'm more familiar with phase 2 2.5 SOHC stuff. You could also try http://opposedforces.com/parts/ and see if the date ranges / codes match up between the two models. But be sure to turn on your notifications for your question/profile cuz there might be some folks who know here.
Yes, but not advised unless you're religious about keeping the 4EAT clean. No.
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