I use a Toyota Passo, whic has 1000cc VVT engine and a Toyota Hilux which has 2700CC EFI engine. The passo does 9km/1 Ltr with 95 octone, within city limits, and the on long trips (ie, Colombo - Dambulla) it does 12km/1 ltr.
the hilux does 5.5 km/1 Ltr within city limits and does 8km/1 ltr on long trips (ie Colombo- Galle)