I have a Cultus 2002. A 50kg CNG cylinder setup was installed many years later. I always refueled from Shell F-7 and got a mileage of approximately 180km per cylinder, summers and winters.
Issue is lots of oil began accumulating in our cars so we boycott it. Also, the compressed gas on the eve of CNG weekends cost more but mileage remained the same.
I now get the car refilled from the HDIP pump in Blue Area/F-7 since the past two months. Mileage is always 140-150 km.
What do you suggest i do to increase the output? There's no way m going back to Shell. Please share your experiences also.