Hi,
guessing these are 34 size steppers about 900 ozin?
Steppers lose torque big time when running fast, at 1000 rpm they are likely to have on 5% of rated torque.
Probably wise to say that max speed is 500 rpm. If you use 5mm pitch ballscrews then max axis speed is 5 times 500=2500mm/min.
You can experiment but this should get you close enuf to start with.
Craig