I have 2.7 I use hi-octane and over the highway get per liter 10+ km & 8.5+ in the city with climate control-
for iranian fuel top-up use your own funnel - stuff the funnel with 3M scotch brite wrapped in malmaal stuffed in funnel, it filters the rust dust & impurities of containers it is stored. keep that funnel in rear along with tools & jack.
In a Corolla I have suffered once over coastal highway I was taking leak bit away & the guy filled 30 liters petrol without any precaution and i was done for next 16 hours, every 10- 15 km i had to removed fuel filter and shake it clean, at reaching winder i got 2 suzuki fuel filters inserted between pump & carb line a 9 hour journey took 16.