The fastest you can propel your ship to is 31. There are however 2 circumstances where you can go faster.
1/ Tractor fast drones to push you (or pull if they are going to a target you want to reach)
2/ Dive into a black hole.
Yes you can do both at once and then use the black hole to "sweep" the tractored drones.
I've used both. Droners hate it when they see you going so fast their drones can't catch you.
Note: You CANNOT tractor probes, photons or plasma torpedoes to pull you to higher speeds. I've tried. I thought it would be funny to "warp" into battle almost immediately and scare the heck out of my opponents
but it didn't work.