@Asim Ali
if we assume that 370rs/48rs cng then u got 7.7kg gas, it means u have 55kg cylinder and it can have 8.5Kg gas, i have 60kg cylinder and my cylinder fills for above 430rs.
if u r getting 115 to 130km from your full cylinder then it is good, not bad to think for tuning it again and chainging system of the car.
regards,