i have 06 vitz on cng with 40 cylinder.
Petrol 1 lit 14 km local wid ac, 16 without ac
17 km long n ac,20 without ac under 120kph
cng 1 tank 90 km local with ac, 110 without ac local
120 km long wid ac, 140 without ac
i use tomasetto adv emu n th car has a problem(rough idling on petrol) runnin on petrol due ecu error, for that i just do a reset by removing -ve terminal for few mins, then on it runs fine on petrol till nex cng refill.