I was very pleased when I found that the FEH would run faster in EV mode than the 25 MPH which was posted in articles I read. I can get to 35 MPH in EV mode, but not often.

If you are going down a hill, 40 MPH is the point which the engine will start. I brake to avoid that.

I think Ford gave us all they could to keep the 2005 FEH reliable. A change to the system could damage it. Look for newer models to make these changes first.