What I neglected to tell Steff is that he probably would have been just fine not rewinding the motor.
My original Bridgeport from 1966 came with a 1 hp motor. Later ones had a 2 hp (I believe).
Since his motor was 480 volt at 2 hp, he could of run it up to 240 volts (linear voltage ramp from 0 to 240 volts and varying the frequency from 0 to 30 hertz) in constant torque mode up to 50% speed and then constant hp mode from 50 to 100% speed (fixed 240 volts but vary the frequency from 31 to 60 hertz).
What does that mean? It means that he would have had rated hp up to 50% speed, but from 50% to 100% speed he would have been limited to 1 hp output. I don't think he ever would have had a problem being limited to 1 hp at the higher speeds.
But too late now!
67 Coronet 500 9.610 @ 139.20 mph
67 Coronet 500 (street car) 13.300 @ 101.75 mph
69 GTX (clone) - build in progress......