If you wire a unipolar 2 phase 8 wire stepper with a bipolar drive in series does each phase see half the voltage? I know the resistance of the motor is 2x and the inductance is 4x. Also know the voltage rating of the motor increases by 1.4x. Pretty sure it still see the supply voltage the same regardless of wiring (unipolar, series, parallel) but I want to make sure.

Looking at running a BP Boss stock stepper with a 120v AC/168v DC drive and I would think the voltage rating in series is 90v or thereabouts. It originally ran 56v at 8.2A unipolar. Read somewhere when wired in series each winding would see 84v so I would be ok. Current would be 6a versus the rated 8.2A for the motor.