Ah, now I see I made a small mistake with my base speed calculation. I forgot to add the 20% base times 17 in impulse drive (and 30% times 15 in hyperdrive) in addition to base, and got a wrong result. Earlier I just divided by the drive level.
Now I'm getting results I expected.
Base speed with impulse is 4000, and with hyperdrive it is 6000.
Now I'm getting results I expected.
Base speed with impulse is 4000, and with hyperdrive it is 6000.