It would be nice if the class 166 has more of acceleration on GWE because it’s hard to keep up with time or give more time on timetable services
Perfectly possible to keep to time on the 166 runs, but you have to know how to drive them As with most diesel MUs the basics are that if you're on dry rails from 0 you stick it straight into notch 5, then about 10mph shove it straight to full power. Stay in full power until you're at line speed. I lose more time on braking than on accelleration, but still usually get gold on a normal run