Category: Basic Configuration
I haven't been able to find what sets the step length and step space for Remora.
At a scale of 1280 steps/mm and a speed of 1800 mm/min you need a step rate of 38kHz. Most stepper drivers are fine with 100kHz (5000ns step and space) and many can go much faster.
I do see a PRU_base_freq setting that defaults to 40kHz. If that is the limit you are hitting then you should be able to manage 1875 mm/min.
If you can do 1870 but not 1880 then that is probably it.