97' Legacy GT Replaced USDM with JDM EJ25

[Mounday]

Hello to all,

New to this forum and by no means a automotive guru either. So thought I would ask all the experts out there in the world.

Blew the motor in my 97' Legacy GT/Automatic. I had it replaced with a JDM EJ25. The motor runs good and no Check Engine light is on. It now idles below 500 when warm, but does not cause problems. It runs and shifts at higher RPM's than I am accustomed to. When it goes into gear it makes a sound as the RPM accelerates and deccelerates. Sounds to my inexerienced ears like it might be the tranny but the tranny worked fine with the old motor. I also have really bad gas mileage now. I'm getting about 15mpg where I was getting somewhere in the low to mid 20's. And last does anyone know what kind of horsepower and torque I'm getting with the JDM or is it the same?

Sorry for the sob story but any advice would be appreciated.