The ideal watering schedule depends on the type of soil as well as natural rainfall. It would be valuable to learn the moisture retention capabilities of your soil and try to maintain the ideal soil moisture level. This link contains excellent information on soil moisture:
http://soilwater.com.au/bettersoils/modules.htm For newly transplanted plants, watering every second day is usually fine, along with shade. After that, twice a week is fine for a loam soil if there is no rain. Rain water is usually better than tap water because it usually is more acidic and has no chemical additives.
If watered too often, the vines may develop shallow roots that could be problematic in a drought.
Passion fruit vines are only productive for approximately two years, so plan on planting a couple every year. They grow huge, 10 meters or more.