I had this setup on my Coupe, and it easily cruised at 60 - 65 MPH. I had it up to 80 MPH and it was still pulling, but unbalanced wheels gave it the shakes so I went no faster. Gas mileage improved and the engine ran cooler.
Please warn us if you do this again, I don't want to be hit by a flying piston or rod!
J Franklin, the motor that did 80 MPH now has over 50,000 miles on it, and it is still strong runner. Model "A' and especially Model "B" motors are tough to destroy.