salaam:
a finely tuned fx engine with proper transmission-oil / tyres / alignment & ofcourse good driving habbits should do atleast 13~14-km/litre in town running.
back in 1985, mine even did 15-km/litre in town. on long run, it used to give 18-km/litre with full load,i.e; four adults and a suit-case on roof-rack.
on cng i don't know the range, as i am against it.
regards