I have bought Toyota Vitz2004 few months ago, it was on petrol and I installed CNG in it. Few days ago I have gotten first chance to drive this car on motorway. The top speed I have recorded on motorway with and without CNG is as follows:
There were 4 persons (of average weight) sitting in the car + a CNG cylinder, so there were 5 persons
125 km/h on pertrol with OD On
140 km/h on pertrol with OD Off
120 km/h on CNG with OD On
130 km/h on CNG with OD Off
I want to ask is this really the normal top speed for this car or it should be more, is there something wrong? Please share your thoughts/experiences on this.