Type of CNG Kits
There are 3 Types CNG Kits available for Sale in India - Open Loop / Close Loop (known as Conventional Kits) and Sequential CNG Kits

If your Car Make is 2009 and Onwards - in most likely scenario - Sequential CNG Kits are considered superior and are Compatible. Pre 2009 Cars - basis Cat Model & Engine Type has both Conventional and Sequential Kits recommended
Sequential CNG Kits
Sequential CNG injection kits are a much better option for cars.

SequentialCNG kits can be installed only on vehicles which have electronic fuel injection systems.

The benefits of these kits are plenty. You can get more accurate CNG injection that results in better mileage and better performance.

It’s a new and a better option today in terms of performance and longevity of engine. These Kits mix the compressed natural gas and air in the right amount for best performance.

Multiple CNG gas injectors manage the flow of the gas for better performance.
Conventional CNG kit
A conventional CNG Kit is a basic manual tuning kit with minimum requirement. There’s no computer to manage the flow of compressed natural gas into the car engine.

The in-uniform flow of CNG is sucked into by the engine that burns inside with the help of spark plugs.

CNG Kit fitted engines were earlier known for poor air-conditioning. But with kits, the performance is much better now.
More and more drivers are now switching to the CNG kit as now the performance is more or less similar and also, the use of Air conditioning does not affect the engine.