Frank
It wasn't me. I'm home fueling up on xxxx.
My C210N with Flint Tanks carries 454 L and running lean of peak averages 53 L / hr Tacho. On long non stop trips it is somewhat better. The longer wings give it more speed than standard when it's hot and high. You can calculate how slow it would have to be before fuel became an issue over a 744 NM trip. We once had a ground speed of 117K Newman to Alice and still had reserves. Another run was Ayers Rock to Rockhampton and we landed with 2+ hours of fuel.