A 44 consumes around 1 litre per minute at cruise power. So - dip the tanks before take-off, convert US g to litres by a rough multiplication of 4, and turn litres into minutes.
Use your watch, use the guages, and watch for the light. And if that isn't enough, get a fuel flow meter fitted so you can monitor fuel useage in flight more accurately than the guages.
In the nicest possible way, where/who taught you ?