[Tom Goldman]

That is a 12% change in gear ratio . not taking into account the probable loss of converter efficiency that will occur , that's a nearly 1000 rpm drop in trap rpm.
Not to mention the loss of reaction time and loss of acceleration coming off the stop.
I'd be talking to your converter guy , maybe looking at a lower stall higher efficiency converter using the existing gear.
You didn't mention what your trap RPM is . ....Is that a concern that it's too high ?