How much the maximum speed for each axis and how can i define it? pls help me

hi

i need to know how much fast every stepper motor on X and Y axis can rotate and how can i define it in config file?
i tried x_axis_max_speed and y_axis_max_speed but when i run the G-code i see no change in speed.
i used to run gcode only from sd card and without PC.
i want to build a CNC machine and i need to know that to choose right ball-screw.
pls help me

best regards