I need to know that the performance of Corolla Altis 1.6 on CNG. I have come to known from different sources that dual VVTI engine is not compatible with CNG. I am aware of the fact that CNG is usually unavailable, so its better not to incorporate it. However, if i do i would like to know whether it works smooth and economical or not. In comparison to this, i have similar views regarding CNG on new modal of Honda city 1.3. A lot of people argue that manual city is compatible with CNG but there will be some issues such as missing on petrol. Kindly share your knowledge and experiences.