Sorry for off topic posting, but I do hope someone could help me.

I have a couple of stepper motors disassembled from old 5.25"
360kB TEAC FDDs (FD-55BR-528-U). Motors work fine, but I do need more
torque, so I am considering building new drivers (using e.g 1207).
I would like to know more about motors.
It seems to me that these are 4 phase 1.8deg motors. There are 5 wires:
yellow, red, brown, blue and white. Brown is common for all windings.
Single winding is 50ohm. The motor is driven via M54534P transistor array.
Can I increase torque by driving more current (how high), what is the winding
sequence?
Thanks for any info.
Janusz