Yep, 50LPH in an IO550 in the cruise and allow 60-65 for the first hour (Rough guess off the top of my head). If the thing is poorly rigged, the speed might suffer, but there are minimum standards to maintain these things to.
If it ran out of fuel, it either had massive head winds or a lack of EMS and a pilot who knows how to operate it and use the red knob appropriately
. My statistics suggest that is >98% of pilots sadly.